CN100505652C - Multi-channel Communication Method in Home Wireless Subnetwork - Google Patents

Abstract

The invention comprises wireless transmitting module and wireless receiving module. The transmitting module executes implements information source coding, modulating and transmitting radio frequency signal. The receiving module implements receiving radio frequency signal, demodulating and decoding etc. multiple wireless transmitting and receiving modules work at same time. Frequency shift keying method is utilized for each wireless transmitting and receiving module, which works at a central carrier frequency point, and bandwidth B of working channel is narrowband. All modules can work at multiple fixed carrier frequency points with bandwidth B. Microprocessor controller generates and receives data information packet and control command information packet, builds and selects channel respectively. The invention provides multiple channels communication method in short distance in high efficiency, having good operating condition and preventing radiofrequency interference.

Description

Multi-channel Communication Method in Home Wireless Subnetwork

technical field

The invention belongs to the technical field of home network, and more specifically relates to the improvement of the multi-channel communication method in the home wireless subnet.

Background technique

The wireless subnet is a subnet in the home application network. The wireless subnet includes multiple wireless modules. In the wireless subnet, these modules exchange control commands and data information through wireless communication. The wireless communication between modules works on a fixed frequency band, which is called a channel.

Generally speaking, the home wireless subnet includes wireless modules and wireless subnet control terminals. There is wireless communication between the modules or between the modules and the wireless subnet control terminal at the same time. There are two topological forms of the home wireless subnet: star topology and peer-to-peer topology.

Home wireless subnets are a new achievement. Based on this patent (technical research), the current home wireless subnet works on a fixed wireless channel, that is, a fixed frequency band.

Like most short-range wireless networks, a home wireless subnet is set up in a limited space. In this limited space, there is more than one wireless network. If all wireless networks only work in a very narrow frequency band, network communication will produce serious radio frequency interference, and even normal communication will not be possible at all.

At the same time, the wireless media environment is also very complex. A set of wireless modules may work well in one particular frequency band, but not in another. Use of alternate channels ensures proper operation. Therefore, multi-channel communication technology is necessary for wireless subnets.

This patent application specifies the working process of multi-channel communication in a wireless subnetwork.

Contents of the invention

The purpose of the present invention is to provide a multi-channel communication method in a home wireless subnet, establish an efficient short-distance wireless network, and introduce multi-working frequency narrowband communication in a home wireless subnet or a wireless home automatic control network; The home wireless subnet has reached a good working condition, and the transmitting module and receiving module can select a good working frequency band to avoid serious radio frequency interference between channels.

In order to achieve the above purpose, the present invention includes the steps of respectively realizing information source coding, modulation and radio frequency signal transmission by multiple wireless transmitting modules and the steps of respectively realizing radio frequency signal reception, demodulation and decoding by multiple wireless receiving modules. It also includes the following steps:

(1) Make each wireless transmitting module and wireless receiving module adopt frequency keying method modulation and demodulation respectively;

(2) Make each wireless transmitting module and wireless receiving module work on the fixed center carrier frequency point of multiple working channels, its bandwidth is narrowband B, and there is a sufficiently wide fixed interval between adjacent two carrier frequency points ;

(3) Use the following sub-steps to select a working channel:

(1) When each wireless transmitting module and wireless receiving module are working, first run the scanning program, scan each channel one by one, and measure the power of the received signal;

(2) If the power of the received signal of this channel is higher than the set threshold, the physical layer will report that the channel is in the "working" state;

(3) If the power of the received signal of this channel is lower than the set threshold, the physical layer will report that the channel is in an "idle" state;

(4) After scanning and running, the wireless transmitting module and the wireless receiving module select an "idle" channel as the initial working channel;

(5) The wireless transmitting module and the wireless receiving module send the information of channel selection to other transceivers, the central node in the home wireless subnet, and at the same time, the central node sends a channel selection command and requires the wireless transmitting module and the wireless receiving module to work on the selected channel;

(6) If the power of the received signal is much lower than the threshold, the receiving module sends a command to the transmitting module to change the communication channel.

In the home wireless subnet, each wireless transmitting module and wireless receiving module is a narrowband modulation system. It works at a center carrier frequency point f, and its working narrowband bandwidth is B. Each working narrowband bandwidth is called a working channel of a home wireless subnet.

Each wireless receiving module can work at multiple fixed carrier frequencies, for example: f ₀ , f ₁ , f _{2 .} . . f _n , f _n+1 , f _n+2 . The bandwidth of each carrier is still B. Therefore, the wireless transmitting module and the wireless receiving module in the home wireless subnet can work on multiple radio frequency channels. Generally, the interval between two radio frequency points in a home wireless subnet is fixed, and the interval must be wide enough to minimize interference between channels.

Each wireless transmitting module and wireless receiving module uses a microprocessor controller to generate and receive data packets and control command packets respectively, and establishes and changes working channels of the wireless transmitting module and the wireless receiving module.

The wireless transmitting module and the wireless receiving module include transmitting (TX) and receiving (RX) channels. The MAC controller (microprocessing controller) generates and receives data packets and control command packets. The TX channel mainly includes transmitter information source coding, modulation mode and RF part of transmission. The MAC controller sends channel control commands to establish and change the working channels of the wireless transmitting module and the wireless receiving module. In the RX channel, the RF section is the RF section of the receiver. The receiver performs demodulation and encoding at baseband. On the RX path, there is energy detection.

The Energy Detection (ED for short) of the received signal is sent to the MAC controller as an important parameter for changing the working channel.

The radio frequency signal receiving step of each wireless receiving module simultaneously detects the energy of the received signal or uses the CSMA/CA algorithm to estimate the state of data transmission of each channel, and the detection result or estimation result is sent to as an important parameter for changing the working channel. The microprocessor controller selects an ideal working channel based on this.

For each wireless transmitting module and wireless receiving module, the channel selection is based on the following two aspects: use the CSMA/CA algorithm to estimate the status of each channel data transmission, or based on the channel quality estimation program, make the wireless subnet The wireless transmitting module and the wireless receiving module select an ideal working channel.

The purpose of the present invention is accomplished like this.

The present invention introduces multiple working channels into the wireless subnet in the home application network; and based on the requirements of the subnet, each wireless transmitting module and wireless receiving module can work in multiple ideal channels; and the channel transmission status and quality estimation is applied to the subnet; each module in the home wireless subnet has a procedure or algorithm for selecting a working channel.

Thus, the present invention increases the efficiency of the operating band. The wireless transmitting module and the wireless receiving module can not only work in a narrowband channel, but also can choose multiple working signal bands. Therefore, the wireless module actually works on quasi-broadband. Based on multiple communication channels, star topology, peer-to-peer network topology and even AD-HOC network can be constructed in the home wireless subnet. The multiple channels of the present invention increase the efficiency of the subnet and reduce the possibility of communication being blocked and disturbed. Multi-channel communication can meet the complexity of the wireless medium. The wireless module in the complex wireless medium can choose the best working frequency channel, which greatly improves the data transmission speed and reliability. The present invention can be widely used in home wireless subnets.

Description of drawings

Fig. 1 is the working principle diagram of the present invention.

Fig. 2 is a block diagram of the working principle diagram of the present invention.

Detailed ways

Embodiment 1. A multi-channel communication method in a home wireless subnet, as shown in FIGS. 1-2 . It includes information source encoding 1, modulation 2 and radio frequency signal transmission 3 steps realized by the wireless transmitting module, and radio frequency signal receiving 4, demodulation and decoding 5 steps realized by the wireless receiving module. It can have multiple wireless transmitting modules and wireless receiving modules working at the same time. Each wireless transmitting module and wireless receiving module adopts the frequency keying modulation method, works at a center carrier frequency point, and the working channel bandwidth B is narrowband. Each wireless transmitting module and wireless receiving module can work at multiple fixed carrier frequency points with a bandwidth of B, for example: f ₀ , f ₁ , f ₂ ...f _n , f _n+1 , f _n+2 (n is a natural number), there is a sufficiently wide fixed interval between two adjacent carrier frequency points.

Each wireless transmitting module and wireless receiving module generates and receives data information packets and control command information packets respectively with the microprocessor controller 6, establishes and changes the working channel of wireless transmitting module and wireless receiving module. The radio frequency signal receiving step of each wireless receiving module simultaneously detects the energy of the received signal or uses the CSMA/CA algorithm to estimate the state of data transmission of each channel, and the detection result or estimation result is sent to as an important parameter for changing the working channel. The microprocessor controller selects an ideal working channel based on this.

The selection method of the working channel at least includes the following steps: (1) when each wireless transmitting module and wireless receiving module work, first run the scanning program, scan each channel one by one, and measure the power of the received signal; (2) if the channel If the received signal power of the channel is higher than the set threshold, the physical layer will report that the channel is in the "working" state; (3) if the received signal power of the channel is lower than the set threshold, the physical layer will report that the channel is in the "working" state; (4) After scanning and running, the wireless transmitting module and the wireless receiving module select an "idle" channel as the initial working channel; (5) The wireless transmitting module and the wireless receiving module send the information of the selected channel to other Transceiver, especially the control terminal in the home wireless subnet, at the same time, the control terminal sends a channel selection command and requires the wireless transmitting module and the wireless receiving module to work on the selected channel; (6) if the power of the received signal is far lower than threshold, the receiving module sends a command to the transmitting module to change the communication channel.

Embodiment 1 provides a multi-channel communication method in a home wireless subnet, establishes an efficient short-distance wireless network, and introduces multi-working frequency narrowband communication in the home wireless subnet; enables the home wireless subnet to achieve a good In the working state, the radiating module and the receiving module can select a good working frequency band to avoid serious radio frequency interference between channels. It can be widely used in home wireless subnets.

Claims (3)

1. A multi-channel communication method in a family wireless subnet, comprising realizing information source coding, modulation and radio frequency signal transmission steps by a plurality of wireless transmitting modules and realizing radio frequency signal reception, demodulation and radio frequency signal reception respectively by a plurality of wireless receiving modules The decoding step is characterized in that it also includes the following steps: (1) Make each wireless transmitting module and wireless receiving module adopt frequency keying method modulation and demodulation respectively; (2) Make each wireless transmitting module and wireless receiving module work on the fixed center carrier frequency point of multiple working channels, its bandwidth is narrowband B, and there is a sufficiently wide fixed interval between adjacent two carrier frequency points ; (3) Use the following sub-steps to select a working channel: (1) When each wireless transmitting module and wireless receiving module are working, first run the scanning program, scan each channel one by one, and measure the power of the received signal; (2) If the power of the received signal of this channel is higher than the set threshold, the physical layer will report that the channel is in the "working" state; (3) If the power of the received signal of this channel is lower than the set threshold, the physical layer will report that the channel is in an "idle" state; (4) After scanning and running, the wireless transmitting module and the wireless receiving module select an "idle" channel as the initial working channel; (5) The wireless transmitting module and the wireless receiving module send the information of channel selection to other transceivers, the central node in the home wireless subnet, and at the same time, the central node sends a channel selection command and requires the wireless transmitting module and the wireless receiving module to work on the selected channel; (6) If the power of the received signal is much lower than the threshold, the receiving module sends a command to the transmitting module to change the communication channel. 2. according to the multi-channel communication method in the family wireless subnet as claimed in claim 1, it is characterized in that each described wireless transmitting module and wireless receiving module all generate and receive data information packet and receiving data packet and The control command information packet is used to establish and change the working channel of the wireless transmitting module and the wireless receiving module. 3. according to the multi-channel communication method in the home wireless subnet according to claim 2, it is characterized in that the radio frequency signal receiving step of each described wireless receiving module all carries out the energy detection of received signal simultaneously or uses CSMA/CA The algorithm estimates the data transmission status of each channel, and the detection result or estimated result is sent to the microprocessor controller as an important parameter for changing the working channel, and the microprocessor controller selects the ideal working channel based on this.

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