CN100403669C - A method of providing real-time broadcast service in mobile communication network - Google Patents

Abstract

The invention relates to a method for providing real-time broadcast service in a mobile communication network, which is realized by setting a dedicated downlink scrambling code. The wireless access network includes the original service layer and the broadcast service layer, which are completely overlapped in the cell structure of the macro cell layer. Each original service layer plus broadcast service layer cell has two scrambling codes, that is, the downlink scrambling code of the original service cell code and the newly added downlink dedicated scrambling code. It is only necessary to add a dedicated downlink scrambling code dedicated to real-time broadcast services in the base station transmitters of each cell in the macro cell coverage layer of the original service, and each cell uses the same downlink dedicated scrambling code and the same dedicated broadcast channel code , only real-time broadcast information is transmitted. The mobile terminal is equipped with channel decoding and source decoding for two types of services. The working mode of the original service remains unchanged, and it works in two working modes of the switchable original service layer and the broadcasting service layer, and shares the information of the original cell. The pilot channel supports real-time broadcasting services in both idle and connected modes.

Description

A method of providing real-time broadcast service in mobile communication network

technical field

The invention relates to the technical field of mobile communication, in particular to a method for realizing real-time broadcasting in a third Code Division Multiple Access (CDMA) mobile communication system, which is a method for providing real-time broadcasting services in a mobile communication network by setting a dedicated scrambling code.

Background technique

In the existing second-generation mobile communication system, limited by the bandwidth, the services provided are relatively simple, such as the main service of transmitting voice signals. In the second-generation semi-mobile communication system, although data services have been developed, they can only be used in information query services due to the limitation of transmission rate. In the future third-generation mobile communication system, multimedia services will be provided, so in the third-generation mobile communication system, multimedia broadcast services and multicast services may also be introduced.

Currently, there are two main ways to provide broadcasting services on mobile terminals:

(1) Integrate a wireless radio or television receiver on the mobile terminal, and use the broadcasting services provided by the existing wireless broadcasting network or television broadcasting network to listen or watch. Its advantage is that it utilizes the existing network resources and does not require any modification to the mobile network, but its disadvantages are also very obvious. Because the mobile terminal needs to integrate a radio circuit or a TV receiver circuit, the cost of the mobile terminal will be greatly increased, especially When integrating a TV receiver, there is a problem that the integration is difficult and the receiving effect cannot be guaranteed.

(2) Utilize the mobile network to provide video-on-demand or audio-on-demand. For example, in the technical specifications of the current third-generation mobile communication system, because there is not enough broadcast channel capacity, the existing broadcast channel can only transmit data with low rate and low real-time requirements. TV programs or radio programs with high real-time requirements can only be provided through user-demand. Its disadvantage is that for some real-time broadcast programs, such as live TV news and sports programs, because each user's order needs to occupy a channel, network resources cannot be shared, resulting in waste of resources. Moreover, limited by resources, it is impossible to meet the needs of a large number of users to watch at the same time.

Contents of the invention

The purpose of the present invention is to design a method for providing real-time broadcasting service in mobile communication network, by setting dedicated broadcasting resource-dedicated scrambling code with wide coverage characteristic in existing mobile network, to provide real-time broadcasting service.

The technical solution for realizing the purpose of the present invention is as follows: a method for providing real-time broadcast services in a mobile communication network, characterized in that:

In the wireless access network of the mobile communication network containing the original service layer, a broadcast service layer dedicated to providing real-time broadcast services is added, and an independent downlink dedicated scrambling code is set in the broadcast service layer, and the location of the broadcast service layer cell and the original service layer cell Overlap to form the original service layer plus broadcast service layer cell structure, each cell uses the same downlink dedicated scrambling code and the same dedicated broadcast channel code, and only transmits real-time broadcast information;

The real-time broadcast service downlink dedicated scrambling code is only added in the macro cell of the non-micro cell or non-pico cell. Scrambling operation, the base station transmitter includes the modulation and spread spectrum of the original service and the modulation and spread spectrum of the real-time broadcast service;

The mobile terminal works in two working modes: the switchable original service layer and the broadcast service layer. The mobile terminal maintains the same working mode for the original service, shares the pilot channel of the original cell, and supports real-time broadcasting business.

The information of the broadcast service layer and the information of the original service layer share one power amplifier or use their own power amplifiers in the base station transmitters of each cell in the coverage layer of the original service macro cell.

The modulation and spread spectrum of the original service includes source coding, channel coding, quadrature phase shift keying, spread spectrum of the original service, and scrambling the spread spectrum result with the downlink scrambling code of each cell; the real-time The modulation and spread spectrum of the broadcasting service include source coding, channel coding, quadrature phase shift keying, spreading and scrambling the spreading result with the downlink dedicated scrambling code for the real-time broadcasting service.

The modulation and spread spectrum of the original service includes source coding, channel coding, quadrature phase shift keying, spread spectrum of the original service, and scrambling the spread spectrum result with the downlink scrambling code of each cell; the real-time The modulation and spread spectrum of the broadcasting service include source coding, channel coding, quadrature phase shift keying, spreading and scrambling the spreading result with the downlink dedicated scrambling code for the real-time broadcasting service.

In the mobile terminal described above, in the demodulation unit of the RAKE receiver, a downlink dedicated scrambling code dedicated to receiving real-time broadcast services is also used, and the channel decoding and deciphering of the original service and the real-time broadcast service are performed in separate channels after the RAKE receiver. Source decoding, the channel code of the RAKE receiver is the dedicated broadcast channel code.

The cell structure of the original service layer plus the broadcast service layer is that the original service layer plus the broadcast service layer cell is consistent with the scope and location division of the original service layer macro cell.

The mobile terminal supports real-time broadcast services in both idle and connected modes, further comprising:

For mobile terminals switched from idle mode to broadcast mode, their original services are still in idle mode;

When the mobile terminal is in a macro cell, it combines the received signals of multiple cells according to the channel estimation results of the cell and the common pilots of one or more macro cells with strong adjacent signals, The signal on the dedicated broadcast channel is demodulated, and the mobile terminal performs cell selection and reselection, location update, and receiving paging information according to the original service flow;

When the mobile terminal is in a micro cell or a pico cell, it is the result of channel estimation based on the common pilots of one or more macro cells with strong adjacent signals, and combines the received signals of multiple cells to solve the problem. The signal on the dedicated broadcast channel is called out, and the mobile terminal performs cell selection and reselection, location update, and receiving paging information according to the original service flow.

The mobile terminal also uses the demodulated dedicated broadcast channel data and known channel transmission conditions, scrambling code and channel code information to estimate the interference of the added downlink dedicated scrambling code on the traffic channel, and obtain the signal from the received signal Subtract the noise value.

The method of the present invention supports real-time, high data rate services, such as real-time broadcast services, by setting dedicated scrambling codes in the existing mobile communication system; when using dedicated scrambling codes, each cell of the broadcast service layer uses the same Scrambling code and channel code; when using a dedicated scrambling code, the broadcast layer + service layer and the original service layer macro cell range and location division are consistent; when using a dedicated scrambling code, the mobile terminal can use the known broadcast service scrambling code, channel Code information, channel estimation information of the local cell and adjacent cells, demodulated broadcast service information, etc., to perform interference cancellation to improve the terminal's ability to receive other service channels; when using dedicated scrambling codes, provide real-time broadcast service operations Providers can activate or deactivate broadcasting service transmission signals as needed.

Compared with prior art, the present invention has the following advantages:

1. The mobile terminal uses the existing functional modules to complete the reception of TV programs and radio broadcast programs, without additional receiving circuits, which improves the integration of the mobile terminal and reduces product costs;

2. Use the existing, wide-coverage mobile network to support real-time broadcast services, which can ensure the effect of the terminal receiving broadcast programs;

3. Compared with program-on-demand and user independent access to broadcast programs, because the same resource supporting real-time broadcast services provides services to multiple mobile users at the same time, the utilization rate of wireless resources and system capacity are improved.

Description of drawings

Fig. 1 is a schematic diagram of a network structure providing real-time broadcasting services in a mobile communication system;

Fig. 2 is a schematic diagram of a cell structure when a separate downlink dedicated scrambling code is used in the present invention;

Fig. 3 is a schematic diagram of the base station transmission process of the downlink dedicated scrambling code setting in the present invention;

Fig. 4 is a block diagram of the system structure and working principle of the mobile terminal in the method of the present invention.

Detailed ways

The present invention provides real-time broadcast service by setting dedicated broadcast resource-special scrambling code with wide coverage in the existing third-generation mobile network.

Referring to Fig. 1, Fig. 1 shows a network structure when a mobile communication system uses dedicated broadcast resources to provide real-time broadcast services. The live sports program is provided to the real-time broadcast service content provider, and the content provider transmits the live sports program to the information transmission server, and then the information transmission server connects it to the mobile communication network, and the air interface of the mobile communication network By setting dedicated broadcast resources, broadcast to mobile terminals in real time. Here, the set dedicated broadcast resources are dedicated scrambling codes. A wired connection may be adopted between the content provider, the information transmission server and the mobile communication network.

Referring to Figure 2, the figure shows the structure and working principle of the wireless access network, which is the system structure after adding the broadcast service mode, that is, the network structure that provides real-time broadcast services by adding dedicated scrambling codes. The dedicated scrambling code for the real-time broadcast service is only used in the macro cell, and the dedicated scrambling code for the broadcast service does not need to be added in the micro cell and the pico cell.

In the technical solution of the present invention to realize real-time broadcast services by setting dedicated scrambling codes, the wireless access network is divided into the original mobile paging service layer and the newly added broadcast service layer. The original service layer provides voice calls, data transmission, For services such as wireless interconnection and video on demand, the added broadcast service layer provides real-time broadcast services.

Since the broadcasting services are completely the same in a certain area, and in the cell layered structure of the third generation mobile communication system (3G), the cells are geographically overlapped with each other, so when implementing the dedicated scrambling scheme, It is only necessary to add a downlink scrambling code dedicated to the broadcast service to the transmitters of each cell in the coverage layer of the original service macro cell. The scrambling code and the channel code of each cell are the same. The scrambling code only needs to transmit broadcast information, and each mobile terminal shares the common pilot channel of the original cell.

Figure 2 shows that under this technical solution, the original service layer and the broadcast layer completely overlap in the cell structure of the macro cell layer. The original service layer is divided into multiple cells. Adjacent cells use different scrambling codes, such as scrambling code 1, scrambling code 2,..., scrambling code 7 in the figure. The original service layer includes uplink physical channels and downlink physical channels. Channels, where the downlink physical channels include common pilot channels, broadcast channels, paging channels and other channels, and these channels are identified by the scrambling codes of the corresponding cells in each cell, such as scrambling code 1 shown in the figure. The broadcast layer is also divided into multiple cells. The cell structure is exactly the same as that of the original service layer. Adjacent cells use the same scrambling code. The downlink physical channels include a dedicated broadcast channel (the other is idle). Each cell is marked with a scrambling code 1'. The combination of the two forms the cell structure of the original service layer and broadcast layer on the macro cell layer. Each cell is equipped with two dedicated scrambling codes, as shown in the figure scrambling code 1+scrambling code 1', scrambling code Code 2+scrambling code 1', ..., scrambling code 7+scrambling code 1'. Among them, scrambling code 1, scrambling code 2, ..., and scrambling code 7 support the original services and remain unchanged, and scrambling code 1' is used to support the newly added real-time broadcasting service.

The above-mentioned structure keeps the original service and the working mode of the mobile terminal unchanged, and the mobile terminal can support real-time broadcasting service at the same time in both the idle mode and the connection mode.

Referring to Figure 3, the figure shows the process of setting the downlink original service scrambling code and downlink dedicated scrambling code by the base station transmitter when transmitting real-time broadcast programs, including the modulation and spread spectrum process of the original service and the modulation of the real-time broadcast service with the spread spectrum process. When setting downlink dedicated scrambling codes, each cell has two scrambling codes, and the scrambling of the original service remains unchanged, that is, the scrambling of the broadcasting service needs to be added. The modulation and spread spectrum of the original service is scrambled with the scrambling code S1 in the multiplier after source coding, channel coding, quadrature phase shift keying (QPSK) and spread spectrum. The modulation and spread spectrum of the broadcasting service are also scrambled with the scrambling code S1' in the multiplier after source coding, channel coding, quadrature phase shift keying (QPSK) and spread spectrum. The adder combines the scrambled results of the two services, and sends them after power amplification by the shared power amplification unit. During implementation, a separate power amplifying unit may also be used for the scrambled results of the two services, and then combined and sent.

The base station transmitter can remove the downlink dedicated scrambling code S1' when there is no broadcast program to be sent, thereby increasing the network capacity.

Referring to Fig. 4, the figure shows the structure and working principle of the mobile terminal implementing the method of the present invention. The terminal includes a master controller 401, a sending unit connected by a source encoder 404, a channel encoder 405, a digital/analog (D/A) converter 406, and a radio frequency (RF) transmitter 407. Receiver 408, analog/digital (A/D) converter 409, frequency synthesizer 412, search module 416, parameter controller 417, RAKE combined receiver 410, automatic frequency correction (AFC) module 411, automatic gain correction (AGC ) module 413, channel decoder 414 of original service, source decoder 415 of original service, channel decoder 414' of broadcasting service, source decoder 415' of broadcasting service, system synchronization module 418 Connect the composed receiving unit, and the antenna 402 and the duplexer 402 shared by the sending unit and the receiving unit.

The mobile terminal that realizes the technical solution of the present invention is based on the existing mobile terminal hardware structure, and then adds a channel decoding module 414' for processing broadcast service scrambling and source decoding after a special RAKE combined receiver 410 Module 415'. The dedicated RAKE combining receiver 410 is used to receive dedicated broadcasting services in addition to receiving original services. The scrambling code 1' and channel code of the demodulation unit of the RAKE combining receiver are dedicated broadcasting channel code S1'. See Figure 4.

The mobile terminal can support the broadcast service in both the idle mode and the connected mode, and the basic process is the same. Taking the idle mode as an example, when the user needs to receive real-time broadcasts, the terminal is switched to the broadcast mode. At this time, the original service of the terminal is still in the idle mode.

When the terminal is receiving broadcast services, if it is in a macro cell, it will perform channel estimation based on the result of channel estimation on the common pilots of this cell and the results of channel estimation based on the common pilots of one or more adjacent macro cells with strong signals , combine the received signals of multiple cells, and demodulate the signals on the broadcast channel. At this time, the terminal can still perform cell selection and reselection, location update, receive paging information, etc. according to the original service flow.

When receiving a broadcast service, if the terminal is in a micro cell or a pico cell, except that the broadcast service cannot be obtained from this cell, other processing is the same as the above case. When the signal quality of the broadcast service cannot meet the service requirement, the cell needs to be reselected to a macro cell to receive the broadcast service.

In order to reduce the interference of the increased downlink scrambling code (such as scrambling code 1' in Figure 2) to other traffic channels in the cell, the mobile terminal can use the demodulated broadcast channel data and known channel transmission conditions, scrambling code, channel Code and other information, estimate the interference of the added downlink scrambling code on the traffic channel, and subtract the interference value from the received signal, so as to improve the receiving performance of other traffic channels.

The method for providing real-time broadcast service in a mobile communication network by setting a dedicated scrambling code of the present invention is especially suitable for carrying out real-time broadcast service in a third code division multiple access (CDMA) mobile communication system.

Claims (7)

1. method that real time broadcasting service is provided in mobile communications network is characterized in that:

In the wireless access network of the mobile radio communication that contains former operation layer, set up to be exclusively used in the broadcasting service of real time broadcasting service layer is provided, establish independently downlink dedicated scrambler at this broadcasting service layer, broadcasting service layer sub-district overlaps with former operation layer subdistrict position, form former operation layer and add broadcasting service layer cell structure, this identical downlink dedicated scrambler is used in each sub-district, dedicated broadcast channel sign indicating number with identical only transmits real-time broadcast message;

Only the macrocell at non-Microcell or non-picocell increases described real time broadcasting service downlink dedicated scrambler, this increase is the scrambling operation that increases described downlink dedicated scrambler in the base station sender of tectal each sub-district of former professional macrocell, and described base station sender comprises the modulation of original business and the modulation and the spread spectrum of spread spectrum and real time broadcasting service;

Portable terminal is by switchable former operation layer and two kinds of mode of operation work of broadcasting service layer, and portable terminal remains unchanged to the working method of original business, shares the pilot channel of original sub-district, supports real time broadcasting service simultaneously under idle and connection mode.

2. a kind of method that real time broadcasting service is provided in mobile communications network according to claim 1, it is characterized in that: the information of described broadcasting service layer and the information of original operation layer, in the base station sender of tectal each sub-district of former professional macrocell, a public power amplifier or use separately power amplifier respectively.

3. a kind of method that real time broadcasting service is provided in mobile communications network according to claim 1 is characterized in that: the modulation of described original business and spread spectrum comprise source encoding to original business, chnnel coding, quaternary PSK, spread spectrum and with each cell downlink scrambler the spread spectrum result are carried out scrambling; The modulation of described real time broadcasting service and spread spectrum comprise source encoding to real time broadcasting service, chnnel coding, quaternary PSK, spread spectrum and with described downlink dedicated scrambler the spread spectrum result are carried out scrambling.

4. a kind of method that real time broadcasting service is provided in mobile communications network according to claim 1, it is characterized in that: described portable terminal, in the demodulating unit of RAKE receiver, also adopt and be exclusively used in the downlink dedicated scrambler that receives real time broadcasting service, with the channel decoding and the source decoding of carrying out original business and real time broadcasting service after RAKE receiver along separate routes, the channel code of RAKE receiver is that channel code is broadcast by described special-purpose factory.

5. a kind of method that real time broadcasting service is provided in mobile communications network according to claim 1, it is characterized in that: described former operation layer adds broadcasting service layer cell structure, is that scope, the position that former operation layer adds broadcasting service layer sub-district and former operation layer macrocell divided consistent.

6. a kind of method that real time broadcasting service is provided in mobile communications network according to claim 1 is characterized in that described portable terminal supports real time broadcasting service simultaneously under idle and connection mode, further comprises:

Switch to the portable terminal of broadcast mode from idle pulley, its original business still is in idle pulley;

When portable terminal is in the macrocell, be according to this sub-district and the result that the public guide frequency of the stronger one or more macrocells of adjacent signal carried out channel estimating, the signal of a plurality of sub-districts of receiving is merged, demodulate the signal on the dedicated broadcast channel, portable terminal carries out cell selecting according to former operation flow and gravity treatment, position are upgraded, paging receiving information;

When portable terminal is in Microcell or the picocell, be the result who carries out channel estimating according to the public guide frequency of the stronger one or more macrocells of adjacent signal, the signal of a plurality of sub-districts of receiving is merged, demodulate the signal on the dedicated broadcast channel, portable terminal carries out cell selecting according to former operation flow and gravity treatment, position are upgraded, paging receiving information.

7. a kind of method that real time broadcasting service is provided in mobile communications network according to claim 1, it is characterized in that: described portable terminal also utilizes the dedicated broadcast channel data that demodulate and known Channel Transmission condition, scrambler and channel code information, estimate the interference of the downlink dedicated scrambler that increased, and from received signal, deduct this interference value Traffic Channel.

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