MXPA06009044A - Multi-hop wireless communications network - Google Patents

Abstract

Systems and techniques are disclosed relating to wireless communications. The systems and techniques involve wireless communications wherein a module or communications device is configured to select first and second terminal pairs, the first terminal pair having a first transmitting terminal and a first receiving terminal, and the second terminal pair having a second transmitting terminal and a second receiving terminal, schedule a first signal transmission from the first transmitting terminal to an intermediate terminal, the first signal transmission being destined for the first receiving terminal, schedule, simultaneously with the first signal transmission, a second signal transmission from the second transmitting terminal to the second receiving terminal, and schedule a power level for each of the first and second signal transmissions that satisfies a target quality parameter for each of the intermediate terminal and the second receiving terminal.

Description

MULTI-SALTO WIRELESS COMMUNICATION NETWORK FIELD OF THE INVENTION The present disclosure generally relates to wireless communications, and more specifically, to various systems and techniques for programming direct and multi-hop communications within a network.

BACKGROUND OF THE INVENTION In conventional wireless communications, an access network is generally used to support communications for a number of mobile devices. An access network is typically implemented by multiple fixed site base stations, dispersed across a geographic region. The geographic region is generally subdivided into smaller regions known as cells. Each base station can be configured to serve all mobile devices in its respective cell. An access network may not be reconfigured easily when there are varied traffic demands across different cell regions. In contrast to the conventional access network, specific purpose networks are dynamic. A specific purpose network can be formed when a number of wireless communication devices, often referred to as terminals, join together to form a network. Terminals in specific purpose networks can operate either as a computer or router. In this way, a specific purpose network can be easily configured to satisfy existing traffic demands in a more efficient manner. In addition, purpose-specific networks do not require the infrastructure required by conventional access networks, which make specific purpose networks an attractive option for the future. Ultra Wide Band (UWB) is an example of a communication technology that can be implemented with specific purpose networks. UWB provides high density communications over a broad bandwidth. At the same time, UWB signals are transmitted by very short pulses that consume very little energy. The output power of the UWB signal is so low that it seems like noise for other RF technologies, making it less interfering. Numerous multiple access techniques exist to support simultaneous communications in a specific purpose network. A Multiple Division Division by Frequency (FDMA) scheme, by example, is a very common technique. FDMA typically involves assigning different portions of the total bandwidth to individual communications between two terminals in the specific purpose network. While this scheme can be effective for uninterrupted communications, better utilization of the total bandwidth can be achieved when constant, uninterrupted communication is not required. Other multiple access schemes include Access Multiple Division by Time (TDMA). These TDMA schemes can be particularly effective for allocating limited bandwidth among a number of terminals that do not require uninterrupted communications. TDMA schemes typically dedicate the entire bandwidth to each communication channel between two terminals at designated time intervals. Code Division Multiple Access (CDMA) techniques can be used in conjunction with TDMA to support multiple communications during each time interval. This can be achieved by transmitting each signal communication in a designated time interval with a different code that modulates a carrier, and consequently, propagates the spectrum of the signal. The transmitted signals can be separated at the receiver terminal by a demodulator using a corresponding code to depropagate the desired signal. The unwanted signals, whose codes do not match, do not deproduct in the bandwidth and contribute only to noise. In a TDMA system that uses propagated spectrum communications to support simultaneous transmissions, a strong and efficient programming algorithm is desired. The programming algorithm can be used to program direct and multi-hop communications, as well as the data rate and the power level of those communications, to avoid excessive mutual interference.

BRIEF SUMMARY OF THE INVENTION In one aspect of the present invention, a method for programming communications includes selecting first and second pairs of terminals, the first pair of terminals has a first transmission terminal and a first receiving terminal, and the second pair of terminals have a second transmission terminal and a second reception terminal, which program a first signal transmission from the first transmission terminal to an intermediate terminal, the first signal transmission is intended for the first reception terminal, which is programmed simultaneously with the first signal transmission, a second signal transmission from the second transmission terminal to the second receiving terminal, and which programs a power level for each of the first and second signal transmissions that satisfy a target quality parameter for each of the intermediate terminal and the second terminal d e reception. In another aspect of the present invention, a communication terminal includes a programmer configured to select first and second pairs of terminals, the first pair of terminals has a first transmission terminal and a first reception terminal, and the second pair of terminals has a second transmission terminal and a second reception terminal, the programmer is further configured to program a first signal transmission from the first transmission terminal to an intermediate terminal, the first signal transmission is intended for the first reception terminal, program simultaneously with the first signal transmission, a second signal transmission from the second transmission terminal to the second receiving terminal, and program a power level for each of the first and second signal transmissions that satisfy a quality parameter objective for each of the intermediate terminal and the second reception terminal. In still another aspect of the present invention, a communication terminal includes means for selecting first and second pair of terminals, the first pair of terminals has a first transmission terminal and a receiving terminal, and the second pair of terminals has a second one. transmission terminal and a second receiving terminal, means for programming a first signal transmission from the first transmission terminal for an intermediate terminal, the first signal transmission is intended for the first receiving terminal, means for programming simultaneously with the first transmission of signal, a second signal transmission from the second transmission terminal to the second receiving terminal, and means for programming a power level for each of the first and second signal transmissions that satisfy a target quality parameter for each of the intermediate terminal and the second receiving terminal. In a further aspect of the present invention, switch-readable media employing a program of instructions executable by a computer program is capable of performing a method for programming communications, the method includes selecting first and second pair of terminals, the first pair of terminals has a first transmission terminal and a first reception terminal, and the second pair of terminals has a second transmission terminal and a second reception terminal, programming a first signal transmission from the first transmission terminal to a intermediate terminal, the first signal transmission is intended for the first receiving terminal, it is programmed simultaneously with the first signal transmission, a second signal transmission from the second transmission terminal to the second receiving terminal, and programming a level of power for each of the first and second transmission it is a signal that satisfies a target quality parameter for each of the intermediate terminal and the second receiving terminal. It is understood that other embodiments of the present invention will become readily apparent to those skilled in the art from the following detailed description., wherein various embodiments of the invention are shown and described by way of illustration. As will be seen, the invention is capable of other different embodiments and its various details are capable of modifications in other various aspects, all without departing from the spirit and scope of the present invention. Accordingly, the drawings and detailed description will be taken as illustrative in nature and not as restrictive.

BRIEF DESCRIPTION OF THE DRAWINGS Aspects of the present invention are illustrated by way of example, and not by way of limitation, in the accompanying drawings, wherein: Figure 1 is a conceptual diagram illustrating an example of a piconet; Figure 2 is a conceptual diagram illustrating an example of a Media Access Control frame (MAC) to control communications between picoredes; Figure 3 is a functional block diagram illustrating an example of a terminal capable of operating without piconet; Figure 4 is a functional block diagram illustrating an example of a baseband processor that operates as a master terminal of the piconet; Figure 5 is a flow chart illustrating an example of operation of a programmer in a baseband processor; Figure 6 is a conceptual block diagram illustrating an example of a picored topology map; and Figure 7 is a functional block diagram illustrating an example of a baseband processor operating with a piconet member terminal.

DETAILED DESCRIPTION The detailed description set forth in conjunction with the accompanying drawings is intended as a description of various embodiments of the present invention and is intended to represent the only embodiments in which the present invention may be practiced. Each mode described in this description is provided only as an example or illustration of the present invention, and should not necessarily be taken as preferred or advantageous over other modalities. The detailed description includes specific details for the purpose of providing a complete understanding of the present invention. However, it will be apparent to those skilled in the art that the present invention can be practiced without these specifics. In some cases, well-known structures and devices are shown in block diagram form to avoid obscuring the concepts of the present invention. Acronyms and other descriptive terminology may be used only for convenience and clarity and is not intended to limit the scope of the invention. In the following detailed description, various aspects of the present invention can be described in the context of a UWB wireless communication system. While these inventive aspects may be well suited for use with this application, those skilled in the art will readily appreciate that these inventive aspects can likewise be applied for use in various other communication environments. Accordingly, any reference to a UWB communication system is intended only to illustrate the inventive aspects, with the understanding that such inventive aspects have a wide range of applications. Figure 1 illustrates an example of a network topology for a piconet in a wireless communication system. A "piconet" is a collection of communication devices or terminals connected using wireless technology in a specific purpose form. The terminals may be stationary or moving, such as a terminal that is carried by a user on foot or in a vehicle, aircraft or ship. The term "terminal" is intended to encompass any type of communication device that includes cellular, wireless or terrestrial phones, personal data assistants (PDA), laptop computers, external or internal modems, PC cards, or any other similar device . In at least one embodiment of the wireless communication system, each pico network has a master terminal and any number of member terminals are enslaved to the master terminal. In Figure 1, a piconet 102 is shown with a master terminal 104 that supports communications between various member terminals 106. The master terminal 104 may be able to communicate with each of the member terminals 106 in the piconet. The member terminals 106 may also be able to communicate with any other terminals under the control of the master terminal 104. The master terminal 104 may communicate with the member terminals 106 using any multiple access scheme, such as TDMA, FDMA, CDMA, or any other multiple access scheme. To illustrate various aspects of the present invention, the wireless communication system shown in Figure 1 will be described in the context of a hybrid multiple access scheme employing both TDMA and CDMA technologies. Those skilled in the art will readily understand that the present invention is not limited in any way to such multiple access schemes. A piconet can be formed in a variety of ways. By means of the example, when a terminal initially turns on, it can look for pilot signals from several picored master terminals. The pilot signal broadcast by each piconet master terminal may be an unmulled propagated spectrum signal, or any other reference signal. Propagated spectrum configurations, a unique pseudo random (PN) noise code for each picored master terminal can be used to propagate the pilot signal. Using a correlation process, the terminal can search through all possible PN codes to identify the master terminal with the strongest pilot signal. If the strongest pilot signal is received with sufficient signal strength to support a minimum proportion of data, then the terminal may attempt to join in the piconet when registering with the master terminator. In some cases, a terminal may be unable to find a pilot signal of sufficient signal strength to support the minimum data rate. This can result from any number of reasons. By way of example, the terminal may be too far away from the master terminal. Alternatively, the propagation environment may be insufficient to support the required data rate. In any case, the terminal may be unable to join an existing piconet, and therefore, may begin to operate as an isolated terminal when transmitting its own pilot signal. The isolated terminal can become the master terminal for a new piconet. Other terminals that are capable of receiving the pilot signal broadcast from the isolated terminal with sufficient resistance can try to acquire that pilot signal and join the piconet of this isolated terminal. The master terminal 104 may use a periodic frame structure to coordinate communications between picoredes. This frame is often referred to in the art as a Media Access Control (MAC) terminal because it is used to provide access to the communication medium to vary terminals. The plot can be of any duration depending on the particular application and the general design restrictions. For discussion purposes, a frame length of 5 ms will be used. A 5 ms frame is reasonable to accommodate a high proportion of 650 Mcps chips and the desire to support data rates of less than 19.2 kbps. An example of a frame structure is shown in Figure 2 with n number of frames 202. Each frame can be divided into 160 or any other number of time slots 204. The interval duration can be 31.25 μs, which corresponds to 20,312.5 chips at 650 Mcps. The plot can dedicate some of its intervals for overload. By way of example, the first slot 206 in the frame 202 can be used to broadcast the spread spectrum pilot signal to all member terminals. The pilot signal may occupy the entire interval 206, or alternatively, be shared in time with a control channel as shown in Figure 2. The control channel occupying the end of the first interval 206 may be a spread spectrum signal broadcast to all member terminals at the same power level as the pilot signal. The master terminal can use this control channel to define the composition of the MAC frame. The master terminal may be responsible for programming communications between picoredes. This can be achieved through the use of one or more additional propagated spectrum control channels that occupy several time slots within the frame, such as time slots 208 and 210 in Figure 2. These additional control channels may be broadcast by the master terminal to all member terminals and include varied programming information. The scheduling information may include assignments of time slots for communications between terminals within the piconet. As shown in Figure 2, these time slots can be selected from the data slot portion 212 of the frame 202. Additional information, such as power level and data rate for each communication between terminals can also be included. The master terminal may also grant transmission opportunities and any given time interval in any number of terminal pairs using the CDMA scheme. In this case, the programming information can also assign the propagation codes to be used for the individual communications between terminals. The master terminal may periodically allocate a fraction of time to homologous transmissions. During this time, the master terminal 104 may assign one of the member terminals 106 to communicate with one or more isolated terminals or adjacent piconets. Those transmissions may require high transmission power, and in some cases, can only be sustained at low data rates. In the case that high power transmissions are needed to communicate with the isolated terminals and / or the adjacent picoredes, the master terminal can decide and not schedule any of the communications between picoredes at the same time. Figure 3 is a conceptual block diagram illustrating a possible configuration of a terminal. As those skilled in the art will appreciate, the precise configuration of the terminal may vary depending on the specific application and the general design constraints. For purposes of clarity and fullness, the various inventive concepts will be described in the context of a UWB terminal with propagated spectrum capability, however, such inventive concepts are likewise suitable for use in various other communication devices. Accordingly, any reference to a UWB terminal of propagated spectrum is intended only to illustrate the various aspects of the invention, with the understanding that the aspects have a wide range of applications. The terminal can be implemented with an input terminal transceiver 302 coupled to an antenna 304. A baseband processor 306 can be coupled to a transceiver 302. The baseband processor 306 can be implemented with a software-based architecture, with any other type of architecture. A microprocessor can be used as a platform to run software programs that, among other things, provide executive control and general system management functions that allow the terminal to operate either as a master or member terminal in a pico network. A digital signal processor (DSP) can be implemented with a layer of improper communication software that executes application-specific algorithms to reduce processing demands on the microprocessor. The DSP can be used to provide various signal processing functions such as pilot signal acquisition, time synchronization, frequency tracking, propagated spectrum processing, modulation and demodulation functions, and non-return error correction. The terminal may also include several user interfaces 308 coupled to the baseband processor 306. The user interfaces may include a keyboard, a mouse, a digital display, and softener, buzzer, vibrator, audio speaker, microphone, camera and / or the like. Figure 4 is a conceptual block diagram illustrating an example of a baseband processor that operates as a terminal teacher. The baseband processor 306 is shown with the transceiver 302. The transceiver 302 may include a receiver 402. The receiver 402 provides detection of the desired signals in the presence of noise and interference. The receiver 402 can be used to extract the desired signals and amplify them to a level where the information contained in the received signal can be processed by the baseband processor 306. The transceiver 302 may also include a transmitter 404. The transmitter 404 may be used to modulate the information of the baseband processor 306 on a carrier frequency. The modulated carrier can be converted upwardly into an RF frequency and amplified to a sufficient power level for the free space radiation through the antenna 304. The baseband processor 306 can enable a 406 programmer when operating as a master terminal . In the software-based implementation of the baseband processor 306, the programmer 406 may be a software program running on the microprocessor. However, as those skilled in the art will readily appreciate, programmer 406 is not limited to this mode, and may be implemented by any means known in the art, including any hardware configuration, software configuration, or combination thereof. , which is capable of performing the various functions described herein. Programmer 406 can be used to program communications between picoredes in a form that utilizes piconet capacity. This can be achieved in a variety of ways. By way of example, programmer 406 can be used to carefully select the terminal pairs that will be coupled with simultaneous communications. Each communication can be made by a direct communication between the pairs of terminals, or alternatively, the communication can be routed through one or more intermediate terminals in the piconet. A communication routed through one or more intermediate terminals will be referred to as "multi-hop" communication. Each of the simultaneous communications can be programmed at a transmission power level that satisfies a target quality parameter for each of the reception terminals. The objective quality parameter may be the carrier-interference ratio (C / I) at the receiving terminal, or any other quality parameter known in the art. Figure 5 is a flow chart illustrating an example of the operation of the programmer. In step 502, the scheduler can be used to select the pairs of terminals that will be paired in communications during the next MAC frame. Initially, the programmer can determine the amount of data that remains to be transmitted between each pair of terminals currently coupled in communications after the current MAC frame. The programmer can also program new calls between pairs of terminals for the next MAC frame. In most cases, the total amount of data that is transmitted to support existing calls, as well as new calls, will greatly exceed what can be transmitted in a single MAC frame. In that case, the programmer can program only a fraction of the data for transmission in the next MAC frame. The amount of data that can be transmitted in the next MAC frame will depend on the various proportions of data that can be supported along with the quality of the wireless medium. Higher data rates tend to increase the amount of data that can be multiplexed by time division in the MAC frame. However, higher data rates also tend to require a higher carrier-to-interference ratio (C / I) to satisfy the minimum QoS requirements, and therefore limit the number of parallel transmissions that can be made. The programmer can be configured in a way that obtains a balance between these two competition factors to maximize the overall capacity of the piconet. The programmer can be used to determine the proportion of data for each new call. The proportion of data selected by the programmer can be based on the type of service requested. By way of example, if a member terminal initiates a call with another member terminal to support a video application, the programmer can determine that the call requires a high proportion of data. If another member terminal indicates a voice call to another member terminal, the programmer may select a lower data rate to support the call. The data rates for existing calls are displayed, and therefore do not need to be recalculated. Programming decisions can be made once the proportion of data for each communication between piconets is determined. These programming decisions can be based on any number of considerations according to any known programming algorithm. By means of the example, programming decisions can be made based on a priority system, where voice communications are given priority over lower latency communications. The programming algorithm can also prioritize transmissions of high proportion of data in an effort to maximize performance. An unbiased criterion that considers the amount of data that is transferred between pairs of terminals and the delay already experienced by such pairs of terminals can also be considered. Other factors can be considered and are within the scope of the present invention. Those skilled in the art will readily be able to adapt to existing programming algorithms for any particular picored application. The programmer can increase the amount of data that can be transmitted in the next MAC frame by programming parallel transmissions. Parallel transmissions must be programmed to maximize data throughput without causing excessive interference. This can be achieved by using a priority-based algorithm to program parallel transmissions at multiple time intervals while maintaining a C / I target-ratio for each receiving terminal. The objective ratio of C / I is the ratio of C / l necessary to support the proportion of data that satisfies the desired QoS. The target ratio of C / I for each receiving terminal for a new call can be calculated from the maximum frame error ratio (FER) by means well known in the art. The objective relations of C / I for existing calls are known, and therefore, do not need to be recalculated. The scheduler may be used for simultaneous communications programs in a manner that satisfies the objective C / I ratio in each of the receiving terminals for a given MAC frame. A picored topology map can be used for this purpose. An example of a picored topology map is shown in Figure 6. The picored topology map can be constructed by the master terminal from transmissions it receives from the member terminals. Returning to Figure 4, a counting module 408 can be used to measure the received signal strength of the member terminals. Since the time and power level of each member terminal transmission is determined by the programmer 406, this information can be provided to the computation module 408, and together with the measured received signal strength, the programmer 406 can be capable of calculate the path loss for each member terminal. The member terminals may also be used to periodically provide the master terminal with path loss measurements to other member terminals in the pico network. These measurements can be based on scheduled transmissions between member terminals. The path loss measurements can be transmitted to the master termination on one or more of the control channels. A signal processor 412 at the receiving end can employ propagated spectrum techniques to extract these measurements from the control channels and store them in memory 410. Returning to Figure 6, a series of dashed lines between the two terminals represents a known distance between two terminals. The distance on the map can be derived from the path loss measurements made at the master terminal, as well as those reported back to it via the member terminals. However, as will be explained in more detail briefly, it is the measured path loss and not the distance that is used for parallel transmission programming decisions. Therefore, if the master terminal having trajectory loss information for each possible combination of terminal pairs in the piconet, then the parallel transmissions can be programmed without having to know the angular coordinates of each member terminal with respect to the terminal. teacher. As a practical matterHowever, a picored topology map with angular coordinates can prove that it is quite useful in programming parallel transmissions. A piconet topology map with angular coordinates can be constructed using any number of techniques including, by way of example, the Navstar Global Positioning Satellite (GPS) navigation system. In this embodiment, each terminal can be equipped with a GPS receiver which is capable of computing its coordinates by means well known in the art. The coordinates for the member terminals can be transmitted to the master terminal on the appropriate propagated spectrum control channel. Returning to Fi 4, the signal processor 412 in the master terminal can employ propagated spectrum processing to extract the coordinates of the terminal and member and provide them to the scheduler 406. The scheduler 406 can use these coordinates, along with its own coordinates, for constructing a picored topology map such as that shown in Fi 6. The scheduler 406 may use the picored topology map to estimate the path loss between pairs of terminals for which the path loss information is not another available form. The path loss is a function of the distance between the terminals and the environmental conditions. Since the path loss between a number of terminals is known, and the distance between the same terminals is also known, the effect of environmental conditions on signal propagation can be estimated by the programmer 406. If we assume that the environmental conditions are relatively the same through the piconet, the programmer 406 may be able to calculate the path loss between terminals for which no track loss information of any other form is available. The results of the path loss calculations can be stored in the memory 410 for later use. In short-range applications, such as UWB, precise estimates of path loss can be made by assuming that the environmental conditions are substantially the same across the piconet. Once the picored topology map is constructed by the scheduler 406 and the path loss information stored to the memory 410, programming decisions can be made. Programmer 406 may utilize the information contained in the picored topology map along with any other appropriate factors that are involved in programming decisions to ensure that communications between picoredes scheduled for the next MAC frame do not unduly interfere with one another . Before describing a methodology to maintain the objective C / l ratio at each receiving terminal in a parallel transmission environment, it is illustrative to examine the impact of the parallel transmissions along with Fi 6. Assume moderate C / I objective requirements through the piconet, a transmission from the member terminal 106a to the member termination 106g can probably be programmed concurrently with a transmission from the member terminal 106c to the member terminal 106e. This programming decision must satisfy the objective C / I requirements because the member terminal 106a should not cause excessive interference to the member terminal 106e, and the transmissions of the member terminal 106c should not cause excessive interference to the terminal. 106g of member. A more aggressive programming decision may also include a transmission from the member terminal 106f to the member terminal 106e. If the objective C / I requirement in member terminal 106d is sufficiently low, this programming decision may not result in excessive mutual interference. However, if the target ratio of C / I in the member terminal 106d is high due for example, to a high data rate application, then the signal strength transmitted from the member terminal 106f may need to be high enough, and as a result, cause excessive interference in the member terminal 106g. This interference can reduce the current C / I ratio in the terminal 106g of member under the target, thereby degrading the performance to an unacceptable level. In this case, the transmission from the member terminal 106f to the member terminal 106d must be scheduled at a different time. Another illustrative example will be described along with a pending transmission from the member terminal 106h to the member terminal 106b. When considering the picored topology map, it should appear that this transmission probably should not be programmed concurrently with the transmission from the member terminal 106a to the member terminal 106g even if the target ratio of C / I in the member terminal 106b It is extremely low. The transmit power in the member terminal 106f needs to exceed the path loss to the member terminal 106b which likely and unduly interferes with the reception of the member terminal 106g. As an alternative processing for scheduling a transmission from the member terminal 106h to the member terminal 106b at a different time, communication can be programmed through one or more intermediate terminals in a multi-hop fashion. By way of example, communication from the member terminal 106h to the member terminal 106b can be routed through the member terminate 106i. In this case, the transmit power of the member terminal 106h can be significantly reduced to accommodate the short distance transmission to the member terminal 106i. This reduction in transmit power in the member terminal 106h results in an increase in the C / I ratio in the member terminal 106g. Depending on the objective C / I ratio in the terminal 106e, the transmission from the member terminal 106h to the member terminal 106i can be programmed concurrently with the transmission from the terminal 106a to the member terminal 106g. The second end of the transmission from the member terminal 106i to the member terminal 106b can be programmed concurrently with the transmission from the member terminal 106a to the member terminal 106b in the next MAC frame. Although the transmit power in the member terminal 106i may need to be increased over the second end of the transmission to overcome the path loss resulting from the distance of the member terminal 106b, the distance between the member terminal 106i and the terminal 106g of member may be sufficient to terminate the resulting interference at a level that satisfies the target ratio of C / I to the member terminal 106g. Returning to Figure 5, the programming algorithm can be used to program the direct communications, in step 504, and the multi-hop communications in step 506, for each MAC frame. This can be achieved in a variety of ways depending on the specific application, the designer's preference and the general design constraints. By way of example, the programming algorithm can use the information contained in the picored topology map in an attempt to schedule performance-maximizing communications, while at the same time giving a certain degree of impartiality between picored terminals. Although the procedures for programming direct and multi-hop communications are shown in Figure 5 by sequentially scheduling direct communications, and then scheduling multi-hop communications, those skilled in the art will appreciate that order can be reversed. Alternatively, the programming of direct and multi-hop communications can be done in parallel. The programming algorithm can also be used to program the transmit power level for each communication in step 508, in a way that maintains the target C / I ratio in each receiving terminal. By way of example, direct communications can be scheduled at each time interval if the target C / I ratio at each receiving terminal can be satisfied. In the case where the target ratio of C / l at each receiving terminal can not be satisfied in a given time interval for simultaneous direct communication between pairs of terminals, then one or more of the communications can be programmed in a multi-way -jump. Alternatively, a decision may be made between a direct or multi-hop communication based on the communication path that requires the minimum total power sum to complete the transmission between the terminal pairs. These multi-hop communications can be routed to several intermediate terminals and sent to their respective destination terminals in a subsequent time interval of the MAC frame. Programming of direct and multi-hop communications for each time slot can involve an interactive process of transmission power calculations to ensure that the target C / I ratio is satisfied by each receiving terminal. An example of this calculation will be provided in the following for a single time slot in the MAC frame with three simultaneous transmissions. Returning again to Figure 6, the three simultaneous transmissions include transmission from the member terminal 106a to the member terminal 106g, a transmission from the member terminal 106c to the member terminal 106e, and finally, a transmission from the terminal 106f from member to member terminal 106b. The C / I ratio (C / IG) in the member terminal 106g can be calculated by the programmer in the master terminal as follows. The signal strength at the member terminal 106g is equal to the transmit power (PA) at the member terminal 106a minus the path loss (LA-G) of the member terminal 106a to the member terminal 106g. The interference in the member terminal 106g results from the signal transmissions by the member terminals 106c and 106f, and may be represented by the transmission power (Pc) in the member terminal 106c minus the path loss (CL-G) from member terminal 106c to member terminal 106g plus transmit power (PF) at member terminal 106f minus path loss (LF-G) from member terminal 106f to member terminal 106g. Based on these relationships, the C / I ratio can be canceled from the logarithmic domain by the following equation: (1) C / IG dB = PA - LA-G - (Pc - Lc-G + PF - F.G + M) where M is equal to an interference margin that can be used to explain the interference outside the piconet. Two similar equations can also be used to calculate the C / I ratios at member terminal receivers 106e and 106b. The ratio of C / I (C / IE) in the member terminal 106e can be calculated in the logarithmic domain by the following equation: (2) C / lEdB = Pc - Lc-E - (PA - LA - E + PF - LF.E + M) where: LC-E is the path loss from member terminal 106c to member terminal 106e; LA-E is the path loss from member terminal 106a to member terminal 106e; and LF-E is the path loss from the member terminal 106f to the member terminal 106e. The ratio of C / I (C / IB) in the member terminal 106b can be calculated in the logarithmic domain by the following equation: (3) C / lEdB = PF - LF-B - (PA - LA_B + Pe - LC-B + M) where: LF-B is the path loss from the member terminal 106f to the member terminal 106b; LA-B is the path loss from the member terminal 106a to the member terminal 106b; and LC-B is the path loss from member terminal 106c to member terminal 106b.

Replace in equations (1) - (3) the objective relations C / I for each of the reception terminals and the path loss information stored in the memory, we are left with three equations and three unknown ones (PA Pc PF ) that can be solved algebraically. Assume that all three equations can be satisfied, then the simultaneous transmissions of the terminal 106a, 106c and 106f of members can be programmed at the calculated power levels. If on the other hand, no combination of power levels can satisfy all three equations, or if any of the required power levels exceeds the maximum transmit power of the terminal, then the programming algorithm can reallocate one or more of the transmissions to an intermediate terminal for a multi-hop communication. With reference to Figure 6, one can easily assure that very likely that some combination of power levels can satisfy all three equations. If the transmit power (PF) is too low, then the target C / I ratio can not be found in the receiving terminal 106b because the signal may be too weak due to the path loss (LP-B). If the transmit power (PF) at the transmit terminal 106f is increased to find the target C / I ratio at the receiving terminal 106b, then the transmission may interfere with the ability of the member terminal 106g to satisfy its target relationship of C / I. As a result, the programming algorithm may decide to reprogram the transmission from the member terminal 106f to the member terminal 106b through an intermediate terminal, such as the member terminal 106d. In another embodiment of the programming algorithm, a decision can be made to program each communication between two terminals that are separated by at least one threshold distance in a multi-hop fashion. This decision can be made before performing a power level calculation. In this case, the programming algorithm can determine that the transmission from the member terminal 106f to the member terminal 106b must be programmed as a multi-hop schedule before calculating the power levels. A decision can be made to route the communication through the member terminal 106d, and then a calculation performed to determine if any combination of power levels can support simultaneous transmissions from the member terminals 106a, 106c and 106f while satisfying the target relations C / I for the 106g, 106e and 106d member terminals. In yet another modality of the programming algorithm, the picored topology map can be consulted before the power level calculation is made. The advantage of this method is that the communication between the member terminals 106f and 106b can automatically guarantee a multi-hop communication just before the distance between the two. By way of example, if the programming algorithm was determined that the transmission of the member terminal 106f to the member terminal 106b must occur concurrently with the transmission from the member terminal 106c to the member terminal 106e, then both transmissions can support itself as direct communications. Also, when it is a transmission from the member terminal 106a to the member terminal 106g it is also programmed at the same time, so that the transmission power of the member terminal 106f becomes problematic. Thus, an algorithm can be easily visualized for those skilled in the art to consider the distance between the two terminals coupled in communications with respect to the terminals in close proximity to the transmission terminals when making an initial programming decision with respect to multi-hop communications before calculating power levels. Once programming decisions are made, they can be transmitted to the member terminals in the piconet on one or more control channels in the next MAC frame. With reference to Figure 4, a signal processor 416 at the transmission end can be used to propagate the programming assignments that are assigned to the transceiver 302 for broadcast to the terminals of various members. Figure 7 is a conceptual flow chart illustrating an example of a terminal with the baseband processor configured with a member terminal. Programmer 406 is shown with imaginary lines illustrating that it is not enabled by baseband processor 306 during operation as a member terminal. The configuration of transceiver 302 is the same if the baseband processor 306 is operating as a master or member terminal, and therefore, will not be discussed further. The transceiver 302 is shown in Figure 7 for fullness. As previously described together with the baseband processor 306 configured as a master terminal, the programming assignments can be distributed to all member terminals in the pico network on one or more control channels. The signal processor 412 at the receiving end can employ propagated spectrum processing to extract the programming information from the control channel and provide it to a controller 418. The schedule information can include the time slot assignments for the various transmissions up to and from the member terminal, as well as the power level and the proportion of data for each one. The programming information may also include a message indicating whether the terminal is an intermediate terminal that supports multi-hop communication. In that case, the time slots for receiving communication from a member terminal and transmitting the communication to another member terminal can also be identified with the corresponding power level of the data rate. The controller 418 may be used to provide the data rate and propagation information of the signal processor 412 at the receiving end for the scheduled transmissions to the member terminal. Using this information, the signal processor 412 can retrieve the communications from other member terminals at the appropriate times and provide the recovered communications to the various user interfaces 408. The intended communications for the retransmission to support multi-hop communications can be stored in the memory 410 until they are scheduled for the retransmission. The controller 418 may also provide power level information to the computation module 408 for each transmission from another terminal. The computation module 408 can also use this information to calculate a path loss from the transmit terminal by using the signal resistance measurement from the transceiver 302 during the scheduled transmissions. The path loss information calculated by the computation module 408 may be stored in the memory 410 and provided to the signal processor 416 at the transmit end for the time programmed for the control channel broadcast. In various terminal modes that employ GPS receiver (not shown), may be used to provide coordinate information to the master terminal on a control channel broadcast by the signal processor 416 and the transceiver 302. The signal processor 416 may be used to propagate communications to various member terminals within the pico network. Communications can originate from the various user interfaces 308 and be stored in a buffer 420 up to the scheduled transmission. At the programmed time, the controller 418 can be used to release the communications from the buffer memory 420 to the signal processor 416 for processing propagated spectrum. The signal processor 416 may also withdraw from the memory 410 various communications for retransmission in a multi-hop form at the appropriate time. The data rate, the propagation code and the transmission power level of the communications can be programmed in the signal processor 416 by the controller 418. Alternatively, the transmission power level can be programmed by the controller 418 in the transmitter 404 by the transceiver 302. The various illustrative logic blocks, modules, and circuits described in conjunction with the embodiments described herein may be implemented or implemented with a general purpose processor, a digital signal processor (DSP), a specific application integrated circuit (ASIC), a programmable field strength (FPGA) or other programmable logic device, discrete gate or transistor logic, discrete hardware components, or any combination thereof designed to perform the functions described herein. A general purpose processor may be a microprocessor, but alternatively, the processor may be any conventional processor, controller, microcontroller, or state machine. A processor can also be implemented as a combination of computing devices, for example, a combination of a DSP and a microprocessor, a plurality of microprocessors, one or more microprocessors together with a DSP core, or any other configuration. The methods or algorithms described in conjunction with the embodiments described herein may be represented directly in hardware, in a software module executed by a processor, or a combination of the two. A software module may reside in a RAM memory, flash memory, ROM memory, EPROM memory, EEPROM memory, registers, hard disks, a removable disk, a CD-ROM, or any other form of storage means known in the art. A storage medium can be coupled to the processor so that the processor can read information from, and write information to, the storage medium. Alternatively, the storage medium can be an integral part of the processor. The processor and storage medium can reside in an ASIC. The ASIC can reside in the terminal or in some other place. Alternatively, the processor and the storage medium may reside as discrete components in the terminal or elsewhere. The prior description of the described embodiments is provided to enable any person skilled in the art to make or use the present invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the generic principles described herein may be applied to other embodiments without departing from the spirit or scope of the invention. Thus, the present invention is not intended to be limited to the embodiments shown herein but should be in accordance with the broadest scope consistent with the principles and novel features described herein.

Claims (33)

1. NOVELTY OF THE INVENTION Having described the present invention, it is considered as a novelty and therefore what is described in the following claims is claimed as property. A method for programming communications, characterized in that it comprises: selecting first and second pairs of terminals, the first pair of terminals has a first transmission terminal and a first receiving terminal, and the second pair of terminals has a second transmission terminal and a second receiving terminal; programming a first signal transmission from the first transmission terminal to an intermediate terminal, the first signal transmission is intended for the first reception terminal; programming simultaneously with the first signal transmission, a second signal transmission from the second transmission terminal to the second receiving terminal; and programming a power level for each of the first and second signal transmissions that satisfy a target quality parameter for each of the intermediate terminal and the second reception terminal.
2. 2. The method in accordance with the claim 1, characterized in that the programming of the first signal transmission further comprises determining that a direct signal transmission from the first transmission signal to the first receiving terminal simultaneously with the second signal transmission does not satisfy an objective quality parameter for the first terminal of reception and the objective quality parameter for the second receiving terminal.
3. 3. The method of compliance with the claim 2, characterized in that the determination that direct signal transmission from the first transmission terminal to the first receiving terminal, simultaneously with the second signal transmission, does not satisfy the objective quality parameters for each of the first and second terminals of reception comprises trying to calculate a power level for each of the first direct signal transmission from the first transmission terminal to the first reception terminal and the second signal transmission that satisfies the objective quality parameter for each of the first and second receiving terminals.
4. The method according to claim 2, characterized in that the determination that the direct signal transmission between the first transmission terminal and the first receiving terminal, simultaneously with the second signal transmission, does not satisfy the objective quality parameters for each of the first and second receiving terminals which is a function of the distance between the first transmission terminal and the first receiving terminal and the distance between the first transmission terminal and the second receiving terminal.
5. The method according to claim 2, characterized in that the determination of the direct signal transmission from the first transmission terminal to the first receiving terminal, simultaneously with the second signal transmission, does not satisfy the objective quality parameters for each of the first and second receiving terminals which is a function of the path loss information between the first transmission terminal and the first receiving terminal and the path loss information between the first transmission terminal and the second terminal of reception.
6. 6. The method of compliance with the claim 5, characterized in that the first and second pairs of terminals are selected from a piconet network.
7. 7. The method of compliance with the claim 6, characterized in that it further comprises constructing a microgrid topology map, and wherein at least a portion of the path loss information is derived from the piconet network topology map.
8. The method according to claim 1, further characterized in that it comprises selecting a third pair of terminals having a third transmission terminal and a third receiving terminal, and programming a third signal transmission between them simultaneously with a retransmission of the first signal transmission from the intermediate terminal to the first receiving terminal.
9. The method according to claim 8, further characterized in that it comprises programming a power level for each of the retransmission of the first signal transmission and the third signal transmission that satisfies a target quality parameter for each of the first and third reception terminals.
10. The method according to claim 1, further characterized in that it comprises programming a different propagation code for each of the first and second signal transmissions.
11. The method according to claim 1, characterized in that the parameter comprises a carrier-to-interference ratio.
12. The method according to claim 1, further characterized in that it comprises transmitting the first signal transmission from the first transmission terminal to the intermediate terminal simultaneously with transmitting the second signal transmission from the second transmission terminal to the second terminal of the second transmission terminal. reception.
13. 13. A communication terminal, characterized in that it comprises: a programmer configured to select the first and second pairs of terminals, the first pair of terminals has a first transmission terminal and a first reception terminal, and the second pair of terminals has a second transmission terminal and a second reception terminal, the programmer is further configured to propagate a first signal transmission from the first transmission terminal to an intermediate terminal, the first signal transmission is intended for the first reception terminal, is programmed simultaneously with the first signal transmission, and a second signal transmission from the second transmission terminal to the second receiving terminal and programs a power level for each of the first and second signal transmissions that satisfy a target quality parameter for each of the first intermediate terminal and the second reception terminal.
14. The communication terminal according to claim 12, characterized in that the programmer is further configured to program the first signal transmission if a direct signal transmission from the first transmission terminal to the first receiving terminal, simultaneously with the second signal transmission, does not satisfy an objective quality parameter for the first receiving terminal and the objective quality parameter for the second receiving terminal.
15. The communication terminal according to claim 13, characterized in that the programmer is further configured to determine that the direct signal transmission from the first transmission terminal to the first receiving terminal, simultaneously with the second signal transmission, does not satisfies the target quality parameters for each of the first and second receiving terminals when trying to calculate a power level for each of the direct signal transmission from the first transmission terminal to the first receiving terminal and the second transmission of the same. signal satisfying the objective quality parameter for each of the first and second receiving terminals.
16. The communication terminal according to claim 13, characterized in that the programmer is further configured to determine that the direct signal transmission between the first transmission terminal and the first receiving terminal, simultaneously with the second signal transmission, does not satisfies the target quality parameters for each of the first and second receiving terminals as a function of the distance between the first transmission terminal and the first receiving terminal and the distance between the first transmission terminal and the second receiving terminal .
17. 17. The communication terminal according to claim 13, characterized in that the programmer is further configured to determine that direct signal transmission from the first transmission terminal to the first receiving terminal, simultaneously with the second signal transmission, does not satisfy the objective quality parameters for each of the first and second receiving terminals as a function of the path loss information between the first transmission terminal and the first receiving terminal and the path loss information between the first transmission terminal and the first receiving terminal.
18. 18. The communication terminal according to claim 17, characterized in that the programmer is further configured to select the first and second pairs of terminals from a picored terminal.
19. 19. The communication terminal according to claim 18, characterized in that the programmer is further configured to construct a network type topology map, and derive at least a portion of the path loss information from the picored topology map. .
20. The communication terminal according to claim 13, characterized in that the scheduler is further configured to select a third pair of terminals having a third terminal of a transmit terminal and a third terminal of reception, and to program a third signal transmission between them simultaneously with a retransmission of the first signal transmission from the intermediate terminal to the first receiving terminal.
21. The communication terminal according to claim 20, characterized in that the programmer is further configured to program a power level for each of the retransmission of the first signal transmission and the third signal transmission that satisfies a quality parameter target for each of the first and third receiving terminals.
22. 22. The communication terminal according to claim 13, characterized in that the programmer is further configured to program a different propagation code for each of the first and second signal transmissions.
23. 23. The communication terminal according to claim 13, characterized in that the parameter comprises a carrier-to-interference ratio.
24. The communication terminal according to claim 13, characterized in that it also comprises a receiver configured to receive communications from a plurality of terminals and a transmitter configured to transmit communications to the plurality of terminals, the programmer is communicatively coupled to the receiver and to the transmitter.
25. 25. The communication terminal according to claim 24, further characterized in that it comprises a reception signal processor configured to disperse communications between the receiver and the programmer, and a transmission signal processor configured to propagate communications between the programmer and the receiver. transmitter.
26. 26. The communication terminal according to claim 24, further characterized in that it comprises a plurality of user interfaces communicatively coupled to the receiver and the transmitter.
27. 27. The communication terminal according to claim 26, further characterized in that it comprises a reception signal processor configured to disperse communications between the receiver and the first of the user interfaces, and a transmission signal processor configured to propagate communications. between the second of the user interfaces and the transmitter.
28. 28. A communication terminal, characterized in that it comprises: means for selecting first and second pairs of terminals, the first pair of terminals has a first transmission terminal and a first reception terminal, and the second pair of terminals has a second terminal of transmission and a second receiving terminal; means for programming a first signal transmission from the first transmission terminal to an intermediate terminal, the first signal transmission is intended for the first reception terminal; means for simultaneously programming with the first signal transmission, a second signal transmission from the second transmission terminal to the second receiving terminal; and means for programming a power level for each of the first and second signal transmissions and satisfying a target quality parameter for each of the intermediate terminal and the second reception terminal.
29. 29. The communication terminal according to claim 28, characterized in that the means for programming the first signal transmission includes means for determining that a direct signal transmission from the first transmission terminal to the first receiving terminal simultaneously with the second signal transmission does not satisfy an objective quality parameter for the first receiving terminal and the objective quality parameter for the second receiving terminal.
30. The communication terminal according to claim 28, further characterized in that it comprises means for programming a different propagation code for each of the first and second signal transmissions.
31. 31. Computer-readable media that represents a program of executable instructions for a computer program for performing a method for scheduling communications, the method characterized in that it comprises: selecting first and second pair of terminals, the first pair of terminals has a first transmission terminal and a first backup terminal, the second pair of terminals has a second transmission terminal and a second reception terminal; programming a first signal transmission from the first transmission terminal to an intermediate terminal, the first signal transmission is intended for the first receiving terminal; programming simultaneously with the first signal transmission, a second signal transmission from the second transmission terminal to the second receiving terminal; and programming a power level for each of the first and second signal transmissions that satisfy a target quality parameter for each of the intermediate terminal and the second reception terminal.
32. 32. The computer readable medium according to claim 31, characterized in that the programming of the first signal transmission further comprises determining that a direct signal transmission from the first transmission terminal to the first receiving terminal simultaneously with the second signal transmission does not satisfy an objective quality parameter for the first receiving terminal and the objective quality parameter for the second receiving terminal.
33. 33. The computer readable medium according to claim 31, characterized in that the method further comprises programming a different propagation code for each of the first and second signal transmissions.