CN1738304A - Method for transmitting high rate data within a MIMO WLAN - Google Patents

Abstract

A method for transmitting high rate data within a multiple input multiple output (MIMO) wireless local area network (WLAN) begins by determining a data transmission rate. The method continues by, when the data transmission rate is between a first data rate and a second data rate, enabling two transmission paths. The method continues by, for each of the two transmission paths, determining at least one of: level of constellation, number of data subcarriers, rate code, and cyclic prefix duration.

Description

The method of transmitting high speed data in the MIMO wireless lan

Present patent application is according to 35USC 119 (e), required name to be called the priority of the temporary patent application of " about speed and the pattern problem of 802.11N ", and its provisional application number is 60/562,206, and provisional application day is on April 14th, 2004.

Technical field

The present invention relates to wireless communication system, more particularly, relate to the collaborative work problem between wireless terminal of future generation and conventional wireless terminals in the wireless communication system.

Background technology

As everyone knows, communication system can be supported in the wireless and wire communication between wireless and/or the wire communication facility.These communication systems comprise the indoor wireless networks of country and/or international cell phone system, internet and point-to-point.Every kind of communication system all is based on one or more communication standards and makes up and work.For example, wireless communication system can come work according to one or more standards, comprising but be not limited to IEEE802.11 (wireless local area network (WLAN) system, WLAN), Bluetooth system, advanced mobile phone service system (AMPS), digital AMPS system, global radio mobile communication system (GSM), code division multiple access (CDMA) system, local multiple spot distribute connecting system (LMDS), multichannel multiple spot to distribute connecting system (MMDS) and/or their variation.

According to the type of wireless communication system, cell phone, two-way radio receiver, PDA(Personal Digital Assistant), PC (PC), kneetop computer, home entertainment device etc. can communicate with other communication equipments directly or indirectly.For direct communication (being also referred to as point to point link), the Wireless Telecom Equipment that participates in work is adjusted to an identical channel or several channel (for example adjusting on one of them of a plurality of radio-frequency carriers of wireless communication system) with its Receiver And Transmitter.With regard to indirect radio communication, each Wireless Telecom Equipment directly communicates by a channel appointed and relevant base station (such as the cellular service) and/or corresponding access point (such as wireless network in indoor or the building).For realizing communicating to connect between the Wireless Telecom Equipment, pass through system controller, public switch telephone network, internet and/or the direct mutual communication of other Wide Area Networks between relevant base station and/or the access point.

Each participates in comprising a built-in transceiver (being Receiver And Transmitter) or connecting a corresponding transceiver (such as wireless communication terminal, radio modem etc. in indoor and/or the building) in the Wireless Telecom Equipment of radio communication.As everyone knows, transmitter comprises a data modulating part, one or more intermediate-frequency sections, and a power amplifier.The data-modulated part is converted to baseband signal according to concrete wireless communication standard with initial data.Described one or more intermediate-frequency section mixes baseband signal and one or more local oscillations to produce radiofrequency signal.Before signal was passed through antenna transmission, described power amplifier amplified the radio frequency signal power.

As everyone knows, receiver links to each other with antenna, comprises a low noise amplifier, one or more intermediate-frequency sections, a filtering part and a data recovered part.Low noise amplifier receives the radiofrequency signal of input by antenna and they is amplified; Described one or more intermediate-frequency section will mix with one or more local oscillations through the radiofrequency signal of amplifying, thereby will be converted to baseband signal or intermediate frequency (IF) signal through the radiofrequency signal of amplifying; Described filtering part is carried out filtering to baseband signal or IF signal, with the undesirable signal de-emphasis in the base band, generates filtering signal; Described data recovered part is recovered initial data to come out from filtering signal according to concrete wireless communication standard.

Wherein, for data are therefrom recovered in the filtering number, the data recovered part has been done a large amount of work.For the receiver of an IEEE802.11a or IEEE 802.11g standard, these work comprise protection gap removal, fast fourier transform, reflection is penetrated with amplitude limit, remove intersection and decode operation.In the decode operation, utilized passage to estimate to generate data recovered the data from going to intersect.According to IEEE 802.11a and/or IEEE 802.11g standard, a frame comprises a short training sequence (STS), a long training sequence (LTS), a signal segment and a plurality of data segment.IEEE 802.11a and/or IEEE 802.11g standard point out that also passage is estimated to finish in the long training sequence stage.In case determined the passage estimation, it will be by the remainder utilization of frame.

At present, developing next generation wlan, it will with IEEE 802.11a, IEEE 802.11b and/or IEEE 802.11g terminal (STA) and access point system (AP) is common exists.Comprise a multiple-input and multiple-output (MIMO) interface (802.11n) in the system of future generation as expected.Described MIMO interface in the system of future generation must with traditional system and base station collaborative work.Collaborative work Capability Requirement legacy equipment can be discerned follow-on transmission and make respective reaction.This collaborative work comprises at least two concrete operations.In first operation, AP supports traditional and terminal of future generation simultaneously.In second operation, the shared channel of conventional terminal and terminal of future generation, just common signal channel/" channel overlap " BSS.In both cases; physical layer convergence process (PLCP) head must allow IEEE 802.11a/b/g terminal can discern transmission of future generation, and by declaring clear channel assessment (CCA) mark or utilizing such as protection mechanisms such as request request/clear to send (RTS/CTS), CTS routers and avoid clashing with described transmission.Under above-mentioned various situations, the energy back compatible of the header of system of future generation is so that legacy equipment can be discerned transmission of future generation.

Next generation communication equipment need satisfy concrete data throughout requirement.One of them requirement is that effective data rate will reach or surpasses 100Mbps.At the PHY of equipment, it is 130Mbps that this switching rate requires.Certainly,, satisfied higher message transmission rate, on signal transmission distance, just hit discount because the power of transmitter is limited.In order to satisfy these requirements, the performance of transmitter and receiver must conscientiously be selected.Thereby the needs of wanting next generation communication system to satisfy these requirements have been produced.

Summary of the invention

High speed data transfers in MIMO WLAN disclosed in this invention has satisfied these requirements fully.In one embodiment, disclose a kind of in multiple-input and multiple-output (MIMO) wireless lan (wlan) the method for transmitting high speed data, wherein at first determine a message transmission rate.Then, when described message transmission rate is between first data rate and second data rate, start two transmission channels.Then, in described two transmission channels each, determine at least one in the following: level of constellation, number of data subcarriers, speed sign indicating number and cyclic prefix duration.

In another embodiment, disclose a kind of support high data rate WLAN method for communicating, wherein at first determined a bandwidth of operation.Determine required data throughput then.Then, select a number of antennas of using with multiple-input and multiple-output (MIMO) baseband signal form.And then select a cluster.Then, according to described bandwidth of operation, number of antennas and cluster, start the work of a MIMO WLAN transceiver, to satisfy required data throughput.

On the one hand, the invention provides the method for transmitting high speed data in multiple-input and multiple-output (MIMO) wireless lan (wlan), comprising:

Determine a message transmission rate;

When described message transmission rate is between first data rate and second data rate, start two transmission channels;

To described two transmission channels each, determine at least one in the following:

Level of constellation (level of constellation);

Number of data subcarriers;

Rate code; And

Cyclic prefix duration.

Preferably, comprise in the step of two transmission channels of described startup:

Activate two antennas that are used for the 20MHz channel.

Preferably, described level of constellation comprises at least one item in the following:

64 quadrature amplitude modulation (QAM);

128QAM; With

256QAM。

Preferably, when level of constellation is 64QAM, comprise at least one in the following in the step of the number of described specified data subcarrier:

From 64 subcarriers, select 52 and be used to transmit data; With

From 64 subcarriers, select 54 and be used to transmit data.

Preferably, when selecting 52 subcarriers, described method comprises:

At each use two pilot subcarriers alternately in described two transmission channels; And

Select one 5/6 rate code.

Preferably, when selecting 54 subcarriers, described method comprises:

At each use two pilot subcarriers alternately in described two transmission channels; And

Use+27 and-27 subcarriers transmit data.

Preferably, when selecting 52 subcarriers, described method comprises:

Simplify cyclic prefix; And

Select one 3/4 rate code.

Preferably, this method also comprises:

Adjust spectrum mask (spectral mask) according to the number of subcarriers of selecting.

Preferably, this method also comprises:

When described message transmission rate owing to the reason of distance during less than first data rate, at 12,24 or the message transmission rate of 48Mbps (megabit per second), starting described two transmission channels uses a code rate less than 3/4 20MHz channel, perhaps, at 27 or the message transmission rate of 54Mbps, start described two transmission channels and use a code rate less than 3/4 40MHz channel.

Preferably, this method also comprises:

When message transmission rate during greater than second data rate, message transmission rate at 192Mbps, startup use 20MHz channel and code rate are four transmission channels of 3/4, at the message transmission rate of 486Mbps, startup use 40MHz channel and code rate are four transmission channels of 3/4.

On the other hand, the invention provides a kind of support high data rate WLAN method for communicating, described method comprises:

Determine a bandwidth of operation;

Determine required data throughput;

Select a number of antennas of using with multiple-input and multiple-output (MIMO) baseband signal form;

Select a cluster; And

According to described bandwidth of operation, number of antennas and MIMO WLAN transceiver of cluster control, to satisfy required data throughput.

Preferably, this method further comprises a definite work code rate; And

Described MIMO WLAN transceiver also comes work according to described work code rate.

Preferably, MIMO WLAN transceiver is supported the baseband signal form of OFDM (OFDM).

Preferably, described OFDM baseband signal form comprises 50 subcarriers, is used to be carried at the interior data of bandwidth of operation of each antenna.

Preferably, OFDM baseband signal form comprises 52 subcarriers, is used to be carried at the interior data of bandwidth of operation of each antenna.

Preferably, this method also comprises:

Determine the cyclic prefix form of a simplification; With

Described MIMO WLAN transceiver also comes work according to the cyclic prefix form of described simplification.

Another aspect, the present invention also provides a kind of transmitter, comprising:

Baseband processing module; And

A plurality of radio frequencies (RF) transmitter, wherein, described processing module is used for:

Determine a message transmission rate;

When described message transmission rate is between first data rate and second data rate, start

Two RF transmitters in described a plurality of RF transmitter;

For described two RF transmitters each, determine at least one in the following:

Level of constellation;

Number of data subcarriers;

Rate code; And

Cyclic prefix duration.

Preferably, described baseband processing module is to start described two RF transmitters in described a plurality of RF transmitter in the following way:

Activation is used for described two RF transmitters of 20MHz channel.

Preferably, described level of constellation comprises at least one item in the following:

64 quadrature amplitude modulation (QAM);

128QAM; With

256QAM。

Preferably, when described level of constellation was 64QAM, described specified data number of sub purpose step comprised at least one in the following:

From 64 subcarriers, select 52 and be used to transmit data; With

From 64 subcarriers, select 54 and be used to transmit data.

Preferably, when selecting 52 subcarriers, described baseband processing module also is used for:

At each use two pilot subcarriers alternately in described two transmission channels; And

Select one 5/6 rate code.

Preferably, when selecting 54 subcarriers, described baseband processing module also is used for:

At each use two pilot subcarriers alternately in described two transmission channels; And

Use+27 and-27 subcarriers transmit data.

Preferably, when selecting 52 subcarriers, described baseband processing module also is used for:

Simplify cyclic prefix; And

Select one 3/4 rate code.

Preferably, described baseband processing module also is used for:

Adjust spectrum mask (spectral mask) according to the number of subcarriers of selecting.

Preferably, described baseband processing module also is used for:

When described message transmission rate owing to the reason of distance during less than first data rate, at 12,24 or the message transmission rate of 48Mbps (megabit per second), starting described two transmission channels uses a code rate less than 3/4 20MHz channel, perhaps, at 27 or the message transmission rate of 54Mbps, start described two transmission channels and use a code rate less than 3/4 40MHz channel.

Preferably, described baseband processing module also is used for:

When message transmission rate during greater than second data rate, message transmission rate at 192Mbps, startup use 20MHz channel and code rate are four transmission channels of 3/4, at the message transmission rate of 486Mbps, startup use 40MHz channel and code rate are four transmission channels of 3/4.

Another aspect, the present invention also provides a kind of transmitter, comprising:

Baseband processing module; With

A plurality of radio frequencies (RF) transmitter, wherein, described processing module is used for:

Determine a bandwidth of operation;

Determine required data throughput;

From described a plurality of radio frequency sending sets, select one with multiple-input and multiple-output (MIMO) baseband signal

The RF transmitter number that form uses is with the RF transmitter that obtains selecting;

Select a cluster; And

Control described selected RF transmitter according to described bandwidth of operation and cluster, required to satisfy

Data throughput.

Preferably, described baseband processing module also is used for:

Determine a work code rate; And

Described selected RF transmitter also comes work according to described work code rate.

Preferably, each selecteed transmitter is all supported the baseband signal form of OFDM (OFDM).

Preferably, described OFDM baseband signal form comprises 50 subcarriers that are used to be transmitted in the data in the selected RF transmitter bandwidth of operation scope.

Preferably, described OFDM baseband signal form comprises 52 subcarriers that are used to be transmitted in the data in the selected RF transmitter bandwidth of operation scope.

Preferably, described baseband processing module also is used for:

Determine the cyclic prefix form of a simplification; With

Described selecteed RF transmitter also comes work according to the cyclic prefix form of described simplification.

Description of drawings

Fig. 1 is the block diagram of a wireless communication system among the present invention;

Fig. 2 is the block diagram of a Wireless Telecom Equipment among the present invention;

Fig. 3 is the block diagram of a Wireless Telecom Equipment among the present invention;

Fig. 4 is the block diagram of the receiver section of Wireless Telecom Equipment shown in Figure 2 among the present invention;

Fig. 5 is the embodiment block diagram of the baseband processing module of Wireless Telecom Equipment shown in Figure 3 among the present invention;

Fig. 6 is another embodiment block diagram of the baseband processing module of Wireless Telecom Equipment shown in Figure 3 among the present invention;

Fig. 7 is another embodiment block diagram of the baseband processing module of Wireless Telecom Equipment shown in Figure 3 among the present invention;

Fig. 8 is an embodiment block diagram of the baseband processing module of Wireless Telecom Equipment shown in Figure 2 among the present invention;

Fig. 9-the 11st, the schematic diagram of the multiple frame format that can handle by baseband processing module shown in Figure 8;

Figure 12 A is can be by a kind of frame format of the processing of baseband module processing module shown in Fig. 7 and 8;

Figure 12 B is the received signal pattern of frame format signal shown in Figure 12 A;

Figure 13 be a plurality of can with the schematic diagram of the header launched on the antenna of Fig. 7 and baseband processing module compatibility shown in Figure 8;

Figure 14 is the transmission mode of frame format shown in Figure 12 A;

Figure 15 is the composition mode of a header of frame format shown in Figure 12 A, and it is applicable to general MIMO transmitter of future generation, is particularly useful for the MIMO transmitter of future generation of double antenna;

Figure 16 is the composition mode of a header of frame format shown in Figure 12 A, and it is applicable to the MIMO transmitter of future generation of triantennary;

Figure 17 is the composition mode of a header of frame format shown in Figure 12 A, and it is applicable to the MIMO transmitter of future generation of four antennas;

Figure 18 is a block diagram, but it shows tradition and next generation wlan equipment is used for explaining the mode of the information of the frame head that is included in a back compatible;

Figure 19 is the frequency characteristic schematic diagram according to multiple MIMO signal format of future generation of the present invention.

Embodiment

Fig. 1 is the block diagram of communication system 10, comprising a plurality of base stations and/or access point 12 and 16, a plurality of Wireless Telecom Equipment 18-32, and a network hardware 34.Described Wireless Telecom Equipment 18-32 can be kneetop computer 18 and 26, personal digital assistant 20 and 30, PC 24 and 32 and/or cell phone 22 and 28.With reference to Fig. 2 wherein Wireless Telecom Equipment is described in detail below.

Base station or access point 12-16 are connected to the network hardware 34 by local area network (LAN) connecting line 36,38 and 40.The network hardware 34 can be router, switch, bridge, modulator-demodulator, system controller etc., and it connects 42 for communication system 10 provides wide area network.Each base station or access point 12 and 16 all have a corresponding antenna or aerial array, with realize with its regional extent in the communicating by letter of Wireless Telecom Equipment, this zone is commonly called basic service set (BSS) 11,13.Usually, Wireless Telecom Equipment in concrete base station or access point 12 or 16 register to receive service from communication system 10.

Usually, the base station is used for cell phone system and similar system, and access point then is used for indoor or the interior wireless network of building.Do not consider the concrete pattern of communication system, each Wireless Telecom Equipment all comprises a built-in transceiver and/or links to each other with a transceiver.This transceiver comprises a ultra-linear amplifier and/or programmable multistage amplifier disclosed by the invention, to be used to strengthen the property, reduce cost, reduce volume and/or reinforcement broadband application.

Wireless Telecom Equipment 22,23 and 24 is positioned at a zone of wireless communication system 10, and they are not related with access point.In this was commonly called the zone of independent based services set (IBSS) 15, Wireless Telecom Equipment carried out direct communication (just point-to-point or point-to-multipoint delivery) by channel appointed, constitutes a special network.

Fig. 2 is the block diagram of a Wireless Telecom Equipment, comprising main process equipment 18-32 and a related transceiver or terminal 60.Concerning the cell phone main frame, transceiver 60 is build-in components.Concerning personal digital assistant main frame, kneetop computer and/or PC, transceiver 60 can be built-in, also can be the outside parts that connect.In the present embodiment, terminal can be adapted to one of them in the multiple wireless lan (wlan) agreement, includes but not limited to IEEE 802.11n.Figure 2 shows that a multiple-input and multiple-output (MIMO) equipment.IEEE 802.11n equipment herein refers to interchangeable next generation wlan equipment, and IEEE 802.11a/b/g equipment then refers to the traditional single output of many inputs (MISO) equipment.Yet, in Fig. 3, will do the MISO equipment that is described in more detail and must use jointly with the MIMO equipment shown in Fig. 2.

As shown in the figure, main process equipment 18-32 comprises processing module 50, memory 52, wave point 54, input interface 58 and output interface 56.Described processing module 50 and memory 52 are carried out the corresponding instruction of being finished by main process equipment usually.Such as, concerning a cell phone main process equipment, processing module 50 is carried out the corresponding communication function according to concrete cellular telephony standard.

Wave point 54 allows data to send to transceiver 60 and receives data from transceiver 60.When the data that receive from transceiver 60 (such as the input data), wave point 54 offers processing module 50 to make further to handle and/or be routed to output interface 56 with data.Output interface 56 is connected on the output display units such as display, watch-dog, loud speaker, the data that receive with demonstration.Wave point 54 also will offer transceiver 60 from the data of handling module 50.Processing module 50 can be passed through the dateout that input interface 58 receives from input equipments such as keyboard, button, microphones, or oneself generates these dateouts.For the data that receive by input interface 58, processing module 50 can be carried out the respective host function and/or will it be routed to transceiver 60 by wave point 54 it.

In transceiver or terminal 60, comprise a host interface 62, baseband processing module 64, memory 66, a plurality of radio frequency (RF) transmitter 68-72, a transmission/reception (T/R) module 74, a plurality of antenna 82-86, a plurality of RF receiver 76-80 and a local oscillating module 100.Baseband processing module 64 combines with operational order in being stored in memory 66, with the function of combine digital receiver and digital transmitter respectively.Intersection, fast fourier transform, cyclic prefix removal, space-time decoding and/or deciphering are penetrated, decode, gone to the digital receiver function including but not limited to digital intermediate frequency to conversion, demodulation, the cluster reflection of base band.The function of digital transmitter is including but not limited to the conversion to intermediate frequency of encryption, coding, intersection, cluster mapping, modulation, inverse-Fourier transform, cyclic prefix interpolation, space-time code and/or digital baseband.Baseband processing module 64 can be realized by one or more treatment facility.Described treatment facility can be microprocessor, microcontroller, digital signal processor (DSP), microcomputer, CPU (CPU), field programmable gate array (FPGA), programmable logic device, state machine, logical circuit, analog circuit, digital circuit and/or any can be according to the equipment of operational order processing signals (analog signal or digital signal).Memory 66 can be single or multiple memory devices, and described memory devices can be read-only memory, random access memory, volatile memory, nonvolatile storage, static memory, dynamic memory, flash memory and/or any equipment that can storing digital information.Be noted that, when processing module 64 realized one or more function by state machine, analog circuit, digital circuit and/or logical circuit, the memory that is used for storing the corresponding operating instruction was to be embedded in the circuit that includes state machine, analog circuit, digital circuit and/or logical circuit.

In the course of the work, transceiver 60 is by the dateout 88 of host interface 62 receptions from main process equipment.Baseband processing module 64 receives dateout 88 according to mode select signal 102, to generate one or more output symbol streams 90.Mode select signal 102 will be indicated a concrete pattern from the model selection table, the back will elaborate to the model selection table.For example, mode select signal 102 may be indicated the frequency band of 2.4GHz, 20 or the channel width of 22MHz and Maximum Bit Rate be 54,000,000/second (MBPS) or higher bit rate, as 122MBPS.In this general type, mode select signal will further be represented a kind of concrete speed.In addition, mode select signal also may be indicated a kind of concrete modulation system, includes but are not limited to Barker code modulation, BPSK (two-phase PSK), QPSK (Quadrature Phase Shift Keying), CCK (complementary code keying), 16QAM (quadrature amplitude modulation) and/or 64QAM.

Baseband processing module 64 can be based on mode select signal 102, and generates one or more output symbols streams 90 from dateout 88.For example, concerning selecteed concrete pattern, if mode select signal 102 expressions have only used a transmitting antenna, baseband processing module 64 will produce single output symbol stream 90.In addition, corresponding with the number of antenna if mode select signal represents to have utilized 2,3 or 4 antennas, baseband processing module 64 will produce 2,3 or 4 output symbol streams 90 from dateout 88.

According to the number of the output symbol stream 90 that produces by baseband module 64, will start the RF transmitter 68-72 of respective number, output symbol stream 90 is converted to output RF signal 92.Transmission/receiver module 74 receives output RF signal 92, and each output RF signal is offered a corresponding antenna 82-86.

When transceiver 60 was in receiving mode, transmission/receiver module 74 received one or more input rf signal by antenna 82-86.T/R mode 74 offers one or more RF receiver 76-80 with input rf signal 94.RF receiver 76-80 flows 96 with the incoming symbol that input rf signal 94 is converted to respective number, and the back is done more detailed the introduction with reference to Fig. 4 to RF receiver 76-80.The number of incoming symbol stream 96 will be corresponding with the concrete pattern of Data Receiving.Baseband processing module 60 receives incoming symbol stream 96 and they is converted to input data 98, will import data 98 by host interface 62 then and offer main process equipment 18-32.For wherein the transceiver or the concrete enforcement of terminal 60, but reference name is called the unexamined patent application of " the WLAN transmitter with high data throughput ", and it is acted on behalf of case and number is BP3516, and the provisional application date is on February 19th, 2004; Also but reference name is called the unexamined patent application of " the WLAN receiver with iterative decoder ", and it is acted on behalf of case number and is BP3529, and the provisional application date is on February 19th, 2004.

In an embodiment of transceiver 60, a kind of in multiple-input and multiple-output (MIMO) wireless lan (wlan) the method for transmitting high speed data can at first determine a message transmission rate.Then, when message transmission rate is between first data rate and second data rate, start two transmission channels.Then, in described two transmission channels each, determine at least one in the following: level of constellation, data subcarriers number, rate code and cyclic prefix duration.

In another embodiment of transceiver 60, a kind of support high data rate WLAN method for communicating can be determined a bandwidth of operation earlier.Can determine the data throughput rate of needs then.Can be applicable to the number of antennas of multiple-input and multiple-output (MIMO) baseband signal form then.Can select a cluster then.According to the number and the cluster of bandwidth of operation, antenna, start the work of MIMO WLAN transceiver then to satisfy the requirement of data throughput.

One of ordinary skill in the art is understandable that Wireless Telecom Equipment as shown in Figure 2 can be realized by one or several integrated circuits.For example, main process equipment can be realized that baseband processing module 64 and memory 66 can realize that the remainder of transceiver 60 is removed antenna 82-86 by second integrated circuit by an integrated circuit, can be realized by the 3rd integrated circuit.As a kind of alternative, transceiver 60 can be realized by an independent integrated circuit.As another alternative, the processing module 50 of main process equipment and baseband processing module 64 can be a common process equipment of realizing on independent integrated circuit.In addition, memory 52 and memory 66 also can realize on an independent integrated circuit, and/or realize that on same integrated circuit processing module 50 and baseband processing module 64 are with as the common process module.

Fig. 3 is the schematic diagram of a Wireless Telecom Equipment, comprising main process equipment 18-32 and respective wireless transceiver 61.Concerning the cell phone main frame, transceiver 61 is build-in components, and concerning personal digital assistant main frame, above-knee main frame and/or personal host computer, transceiver 61 can be a build-in components, also can be external component.The working method of main process equipment 18-32 is explained with reference among above-mentioned Fig. 1.Wlan device among Fig. 3 may be according to the standard operation of a certain or several IEEE 802.11a/b/g, as with Fig. 2 in the difference of MIMO equipment, shown in Figure 3 is MISO equipment.

Transceiver 61 comprises: host interface 62, baseband processing module 64, analog to digital converter (ADC) 111, filtration module 109, intermediate frequency (IF) mixes down conversion module 107, module 101 accepts filter, low noise amplifier 103, transmission/reception modular converter 73, local oscillating module 74, memory 66, digital transmitter processing module 76, digital to analog converter (DAC) 78, filtration module 79, intermediate frequency (IF) up-conversion (conversion) module 81, power amplifier 83, transmitter filtration module 85 and antenna 86.Antenna 86 can be by transmitting and receiving the shared individual antenna that is subjected to 73 controls of Tx/Rx modular converter of passage; Or be respectively applied for the separate antenna of transmission channel and receive path.The enforcement of antenna depends on the specific criteria that Wireless Telecom Equipment need be deferred to.Baseband processing module 64 is by afore-mentioned work, and the one or more functions shown in the execution graph 5-19.

During work, the dateout 88 that transceiver 61 receives from main process equipment by host interface 62, host interface 62 is routed to baseband processing module 64 with dateout 88, according to concrete wireless communication standard (as IEEE.802.11a/b/g, bluetooth etc.), baseband processing module is handled dateout 88, and generates output time domain base band (BB) signal.

Digital to analog converter 77 will be exported the time domain baseband signal and be transformed into analog domain from numeric field.Filtration module 79 at first carries out filtering to analog signal, then they is offered IF up-conversion module 81.Based on the transmitter local oscillations 83 that is provided by local oscillating module 100, IF up-conversion module 81 is the RF signal with analog baseband signal or low frequency IF conversion of signals.The RF signal generates output RF signal 92 through power amplifier 83 amplification RF signals, and output RF signal 92 is via 85 filtering of emission filtration module.Output RF signal 92 sends to base station, access point and/or other radio communication terminals by antenna 86.

Transceiver 61 also receives the input rf signal 94 that is sent by base station, access point or other Wireless Telecom Equipments by antenna 86.Antenna 86 offers the module 101 that accepts filter to input rf signal by Tx/Rx modular converter 73.Rx filtration module 71 is input rf signal 94 bandpass filterings, and will offer low noise amplifier 103 through the RF signal of filtering, and low noise amplifier amplification RF signal 94 generates the input rf signal through amplifying.Low noise amplifier 72 will offer IF down conversion module 107 through the input rf signal that amplifies.According to the receiver local oscillations 81 that is provided by local oscillating module 100, the IF down conversion module directly is converted to the input rf signal that amplifies low IF signal of input or baseband signal.Down conversion module 70 will be imported low IF signal or baseband signal offers filtering/gain module 68, and low IF signal of 109 pairs of inputs of filtration module or the filtering of input baseband signal generate the input signal through filtering.

Analog to digital converter (ADC) 111 will be converted to input time domain baseband signal through the input signal of filtering.According to the concrete wireless communication standard of being carried out by transceiver 61, baseband processing module 64 will import time domain baseband signal decoding, deciphering, reflection is penetrated and/or be demodulated into and recapture (recaptured) and import data 98.The input data 98 that host interface 62 will be recaptured by wave point 54 offer main process equipment 18-32.

Concerning the those skilled in the art in present technique field, the Wireless Telecom Equipment of understanding easily as shown in Figure 3 can be realized by one or several integrated circuits.For example, main process equipment can be realized by an integrated circuit (chip); Baseband processing module 64 and memory 66 can be realized by second integrated circuit; The remainder of transceiver 61 is removed antenna 86, can be realized by the 3rd integrated circuit.As another embodiment, transceiver 61 can be realized by an independent integrated circuit.As another embodiment, the processing module 50 of main process equipment and baseband processing module 64 can be the common process equipment of realizing on an independent integrated circuit.In addition, memory 52 and memory 66 also can be realized on an independent integrated circuit, and/or realize on the same integrated circuit of the common process module that realizes processing module 50 and baseband processing module 64.

Fig. 4 is the block diagram of RF receiver 76-80.In the present embodiment, each RF receiver 76-80 comprises a RF filter 101,105, down conversion module of 103, programmable gain amplifiers of low noise amplifier (LNA) (PGA) 107, analog filter 109, analog to digital converter module 111, digital filter and to down sample module 113.Described RF filter 101 can be a high freguency bandpass filter, receives input rf signal 94 and with its filtering, generates the input rf signal through filtering.Be provided with based on gain, the input rf signal 94 that low noise amplifier 103 amplifies through filtering, and will offer programmable gain amplifier 105 through amplifying signal.Programmable gain amplifier amplifies input rf signal 94, then they is offered down conversion module 107.

Down conversion module 107 comprises: a plurality of frequency mixers, a summation module, a filter that is used to mix input rf signal and local oscillations (LO) generate analog baseband signal.Described local oscillations (LO) is provided by local oscillating module.Analog filter 109 is analog baseband signals, and they are offered analog-to-digital conversion module 111, is converted to digital signal.Digital filter and carry out filtering to 113 pairs of digital signals of down sample module is regulated sample frequency then and is generated incoming symbol stream 96.

Fig. 5 is that the function of baseband processing module 64 as shown in Figure 3 realizes block diagram.In the present embodiment, the realization of baseband processing module 64 comprises: protection gap remove module 130, fast Fourier transform (FFT) module 132, reflection penetrate/amplitude limit module 134, one remove Cross module 136, a decoder module 138 and a channel estimation module 120.In the present embodiment, described channel estimation module 120 comprises a coding module 140, Cross module 142, mapping block 144, a channel estimation module 146 and a channel estimating update module 148.Also illustrate among the figure one may be consistent with IEEE802.11a and/or IEEE 802.11g frame 155, described frame comprises a short training sequence, two long training sequences, a service data section and a plurality of data payload section.

Each section of baseband processing module 64 processed in sequence frames 155.As everyone knows, baseband processing module 64 is handled the existence that short training sequences are discerned a frame, begin to determine this frame whether effectively, and determine the initial yield value (gain of for example LNA gain, programmable gain amplifier and modulus (conversion) gain etc.) of wireless receiver part.

Then, baseband processing module 64 is handled long training sequence, further determines the validity of frame 155, and removes the protection gap that module 130 removes the separation long training sequence by the protection gap.Fast fourier transform module 132 will represent that the time-domain signal of long training sequence is converted to a plurality of time-domain signals 150.Reflection penetrates/and amplitude limit module 134 penetrates frequency-region signal 150 reflection, generates reflection and penetrates signal 152.Cross module 136 is penetrated reflection at signal 152 and is gone to intersect, and generates and goes to intersect data 154.Decoder module 138 is decoded and is gone to intersect data 154, generates input decoded data 98.

For example, if baseband processing module 64 and IEEE 802.11a and/or 802.11g compatibility, then importing the time domain baseband signal is 5GHz and/or interior OFDM (OFDM) modulation signal of 2.4GHz frequency band range.FFT module 132 is converted to a series of frequency-region signal with time-domain signal, and each frequency-region signal is represented the subcarrier of a channel.As everyone knows, in 802.11b and/or 802.11g standard, 52 non-zero subcarriers of each channel have 48 data subcarriers and 4 pilot subcarriers.Remaining 12 subcarrier all is zero, and at least one protection gap section is provided.Each signal is represented the data through PBSK, QPSK, 16QAM and/or 64QAM modulation.The anti-corresponding signal that is mapped as is determined concrete symbolic vector, and then, corresponding signal goes to intersect by removing Cross module 136.Decoder module 138 (can be a Viterbi decoder) receives the symbolic vector of representing modulating data; And according to the bit value decoding symbols vector of recapturing, described bit value is represented by the cluster mapping symbols.

From in essence, channel estimation module 120 has repeated the function of baseband transmission, will be mapped as frequency-region signal again by the decoded data that decoder module 138 produces.As shown in the figure, coding module 140 can be that speed is 1/2 convolution coder, and input decoded data 98 is encoded, and generates through coded data 156 again.What in fact, coding module 140 was carried out is the decoder module 138 opposite encoding functions identical with the transmitting antenna communication equipment.

Cross module 142 coded data 156 again intersects, and generates to intersect data 158 again.Mapping block 144 will intersect data 158 again and be mapped as a series of frequency-region signal 160 that shines upon again.These functions all are that reflection is penetrated/amplitude limit module 134 and the reverse or the concord of going Cross module 136 functions.

Channel estimation module 146 utilizes a series of frequency-region signal 160 and the frequency-region signal 150 of shining upon again, for the concrete part at processed frame just generates channel estimating 162.Channel estimating 162 can be the long training sequence utilization, generate a LTS channel estimation value, also can be the service segment utilization, generate a service segment channel estimation value, described service segment is often referred to the section as frame information, therefore, the payload of one or more data all may have its channel estimation value of determining 160.

Channel estimating update module 148 receive channels estimate 162, are used for the physical segment of frame 155, and the channel estimation value before upgrading generates a channel estimating 163 through upgrading.Concerning the those skilled in the art in present technique field, to understand easily, the LTS channel estimation value is to obtain according to former WLAN receiver channel estimation technique, described WLAN receiver is applicable to 802.11a and/or 802.11g standard.

Reference frame 155, based on the LTS channel estimating, channel estimation module 120 generates a channel estimation value for this frame.After receiving service segment, channel estimation module 120 generates a service segment channel estimation value for service segment.Then, according to initial channel estimation value and the new service segment channel estimation value of determining, channel estimation module 120 upgrades the channel estimation value 163 of this frame.After receiving the first data payload, channel estimation module 120 is that this data payload generates a relevant channel estimation value, utilizes this first payload channel estimation value to upgrade channel estimation value in the past then.Channel estimation module 120 can be determined a corresponding channel estimation value for each data payload that receives, and upgrades current channel estimation value 163.In addition, channel estimation module 120 can only utilize a plurality of data payload sections to determine the renewal of channel estimating 163.The described data payload of using (for example can pre-determine, with each the 4th data payload as this data payload), perhaps the data payload is determined according to corresponding data payload capability, and this energy level need surpass the energy threshold value that is used to upgrade channel estimating.

The example of channel estimation module 146 and channel estimating update module 148, the FFT that receives exports K ^ThSignal is:

Y _k＝Z _kH _kz+V _k

When leftover bits and pieces k was applicable to any signal, equation was:

Y＝ZH+V≈CN(0，σ ²)

Wherein, Y is frame information section that receives and/or the payload section that receives; H is corresponding channel estimating; V represents the noise section of frame information section that receives and/or the payload section that receives; Z represents a plurality of frequency-region signals that shine upon again of frame information section that receives and/or the payload section that receives; Wherein Z can be expressed as: Z=K _MODX.Therefore, following formula also can be expressed as:

Y＝(Z _i+jZq)(Hi+jHq)+(Vi+jVq)

＝(Z _iHi-ZqHq)+j(ZqHi+ZiHq)+(Vi+jVq)

So

Yi＝ZiHi-ZqHq+Vi

Yq＝ZqHi+ZiHq+Vq

So

ZiYi+ZqVq＝(Zi ²+Zq ²)Hi+ZiVi+ZqVq，

Like this, channel estimation value can be expressed as:

${\hat{H}}_{\mathrm{DNi}}={\hat{H}}_i=\frac{Z_i{Y}_i+Z_q\mathrm{<figure-callout\; id="2"\; label="Vq\; Z\; i"\; filenames="A20051006740400472.png,A20051006740400481.png"\; state="\{\{state\}\}">Vq</figure-callout>}}{{Z_i}^{}}$

${\hat{H}}_i=H_i+\frac{Z_i{V}_i+Z_q\mathrm{<figure-callout\; id="2"\; label="Vq\; Z\; i"\; filenames="A20051006740400472.png,A20051006740400481.png"\; state="\{\{state\}\}">Vq</figure-callout>}}{{Z_i}^{}}$

$=\frac{{{\mathrm{<figure-callout\; id="2"\; label="Z\; i"\; filenames="A20051006740400472.png,A20051006740400481.png"\; state="\{\{state\}\}">Z</figure-callout>}}_i}^2{\mathrm{\&sigma;}}^2+{{\mathrm{<figure-callout\; id="2"\; label="Z\; q"\; filenames="A20051006740400472.png,A20051006740400481.png"\; state="\{\{state\}\}">Z</figure-callout>}}_q}^2{\mathrm{\&sigma;}}^2}{{({{\mathrm{<figure-callout\; id="2"\; label="Z\; i"\; filenames="A20051006740400472.png,A20051006740400481.png"\; state="\{\{state\}\}">Z</figure-callout>}}_i}^2+{Z_q}^2)}^2}$

$=\frac{{\mathrm{\&sigma;}}^2}{{({{\mathrm{<figure-callout\; id="2"\; label="Z\; i"\; filenames="A20051006740400472.png,A20051006740400481.png"\; state="\{\{state\}\}">Z</figure-callout>}}_i}^2+{Z_q}^2)}^2}$

$=\frac{{\mathrm{\&sigma;}}^2}{{K_{\mathrm{MOD}}}^2({{\mathrm{<figure-callout\; id="2"\; label="X\; i"\; filenames="A20051006740400472.png,A20051006740400481.png"\; state="\{\{state\}\}">X</figure-callout>}}_i}^2+{X_q}^2)}$

The another one example has high-octane cluster point and the estimated value noise can be reduced to minimum.For example, during 64QAM (quadrature amplitude modulation), K _Mod=1/42, then

$\frac{{\mathrm{\&sigma;}}^2}{{K_{\mathrm{MOD}}}^2({{\mathrm{<figure-callout\; id="2"\; label="X\; i"\; filenames="A20051006740400472.png,A20051006740400481.png"\; state="\{\{state\}\}">X</figure-callout>}}_i}^2+{X_q}^2)}=\frac{{42\mathrm{\&sigma;}}^2}{({{\mathrm{<figure-callout\; id="2"\; label="X\; i"\; filenames="A20051006740400472.png,A20051006740400481.png"\; state="\{\{state\}\}">X</figure-callout>}}_i}^2+{X_q}^2)}$

From then in the example as can be seen, only just carry out the renewal of passage estimated value greater than 42 the time when the cluster energy, under this hypothesis prerequisite, following cluster coordinate provides such energy rank correspondence table:

(X _i，X _q) X _i ²+X _q ²

I1，I7 50

I3，I7 58

I5，I7 74

I7，I7 98

I5，I5 50

Fig. 6 is the another kind of implementation of baseband processing module 64.In this embodiment, baseband processing module comprises: the protection gap removes module 130, FFT module 132, reflection and penetrates/amplitude limit module 134, remove Cross module 136, decoder module 138 and channel estimation module 120.In the present embodiment, channel estimation module 120 comprises: Cross module 142, mapping block 144, channel estimation module 146 and channel estimating update module 148.The function of module 130-138 is used for input time domain baseband signal is converted to input decoded data 98 with reference to aforementioned explanation to Fig. 5 appropriate section.

In the present embodiment, channel estimation module 120 receives by Cross module 142 and goes to intersect data from module 136.Cross module 142 intersects data once more, produces to intersect data 158 again.Mapping block 144 will intersect data 158 again and be mapped as a series of frequency-region signals 160 that shine upon again.The effect of channel estimation module 146 and channel estimating update module 148 is used to produce the channel estimating 163 through upgrading with reference to aforementioned explanation to Fig. 5 appropriate section.

Fig. 7 is another embodiment of baseband processing module 64.In this embodiment, the configuration of baseband processing module 64 comprises: the protection gap removes module 130, FFT module 132, reflection and penetrates/amplitude limit module 134, remove Cross module 136, decoder module 138 and channel estimation module 120.In this embodiment, channel estimation module 120 comprises: mapping block 144, channel estimation module 146 and channel estimation value update module 148.The effect of module 130-138 is used for input time domain baseband signal is converted to input decoded data 98 with reference to aforementioned explanation to Fig. 5 appropriate section.

The present embodiment, channel estimation module 120 receives reflection by mapping block 144 and penetrates signal 152.Mapping block 144 is penetrated reflection at signal 152 and is mapped as ofdm modulation signal, generates a plurality of frequency-region signals 160 that shine upon again.The function of channel estimation module 146 and channel estimating update module 148 is used to generate the channel estimating 163 through upgrading with reference to aforementioned explanation to Fig. 5 appropriate section.

Fig. 8 is the Base-Band Processing schematic diagram that meets Wireless Telecom Equipment receiver shown in Figure 2.Base-Band Processing comprises: in the time of one/empty decoder 294, a plurality of fast Fourier transform (FFT)/cyclic prefix remove module 296-300, the reflection of a plurality of symbol penetrate module 302-306, multiplexer 308, one remove interleaver 310, channel decoder 312, a decipher 314 and a channel estimation module 120.Baseband processing module also can comprise: a schema management module 175, this module be based on the pattern of operation input 313, generates to be provided with 315 and rate selection 311.The time/empty decoder module 294 receives the P-input from receiver channel, and generation M-output signal.In one embodiment, the time/empty decoder module 294 in, the input of carrying out each passage meets the decoding matrix computing of multiply by following form:

$\left[\begin{array}{ccccc}{C}_1& C_2& C_3& \&CenterDot;\&CenterDot;\&CenterDot;& C_{2M-1}\\ -{\mathrm{<figure-callout\; id="2"\; label="C"\; filenames="A20051006740400472.png,A20051006740400481.png"\; state="\{\{state\}\}">C</figure-callout>}}_2^{<figure-callout\; id="1"\; label="*\; C"\; filenames="A20051006740400391.png,A20051006740400431.png"\; state="\{\{state\}\}">*</figure-callout>}& C_{}^{}{}_1^{<figure-callout\; id="4"\; label="*\; C"\; filenames="A20051006740400391.png"\; state="\{\{state\}\}">*</figure-callout>}& C_{}{}_4& \&CenterDot;\&CenterDot;\&CenterDot;& C_{2M}\end{array}\right]$

The number that is noted that the row of decoding matrix and input channel is corresponding, the number correspondence of row and output channel.The number of space-time decoding M output channel can equal the number of space-time decoding P-input channel, and perhaps input channel P number equals the M+1 port number.

The FFT/ cyclic prefix is removed module 296-300 M symbols streams is transformed into frequency domain from time domain, generates M time-domain symbol stream.In a specific embodiments, precoding is removed function and is eliminated the internal symbol interference based on certain precoding.Be noted that generally 64 point (64-point) FFT are used for the channel of 20MHz, and 128 FFT is used for the 40MHz channel.

It is data bit stream with the frequency domain symbol information translation that module 302-306 is penetrated in the symbol reflection.An embodiment, individual symbol reflection is penetrated module and will be mapped as a data bit stream through the symbol (for example, BPSK, QPSK, 16QAM, 64QAM, 128QAM etc.) of quadrature amplitude modulation (QAM).Be noted that IEEE 802.11 (a), may use two Gray codes for back compatible.Multiplexer 308 will be compound through the reflection symbols streams of penetrating is an independent passage.Go 310 pairs of these single passages of interleaver to go to intersect.

Iterative decoder 312 is decoded and is gone to intersect data, the generating solution code data.In unexamined patent application " the WLAN receiver with iterative decoder " more detailed description is arranged, the case number acted on behalf of of this application is BP3529, and it is 2/20/04 that provisional application is submitted the date.Decipher 314 generates input data 98 with the decoded data deciphering.In one embodiment, decipher 314 (in GF2) is removed the pseudo random sequence in the decoded data.Pseudo random sequence may be from feedback shift register, and this shift register has multinomial S (x)=x ⁷+ x ⁴+ 1 generator, the generating solution ciphertext data.

Channel estimation module 120 can link to each other with the output of removing Cross module 310, receives to go to intersect data, and perhaps the output with channel decoder 312 links to each other, and receives decoded data.If the connection of channel estimation module 120 is used to receive decoded data, its function is with reference to the explanation of corresponding component in the earlier figures 5.Go to intersect data if the connection of channel estimation module 120 is used for receiving, its function is with reference to the explanation of corresponding component in the earlier figures 6.

Fig. 9 is the schematic diagram of frame 200.In at the regional level, be used for radio communication have only the IEEE802.11n compatible equipment time, shown frame 200 can be constructed according to IEEE 802.11n.As shown in the figure, frame 200 comprises: a short training sequence (STS) 157, a plurality of additional long training sequence (suppl LTS) 201-203 and a plurality of data payload section 205-207.For the frame of this form, the channel estimation module 120 among Fig. 8 will at first generate channel estimation value according to the LTS channel estimating as 5 pairs of appropriate section explanations of earlier figures.Then, channel estimation module 120 upgrades each channel estimation value.As shown in the figure, the first data payload has a corresponding channel estimation value, is used to upgrade the LTS channel estimating, generates the channel estimation value through upgrading.Next data payload has another corresponding channel estimation value again, and this corresponding channel estimation value is used to upgrade the channel estimation value of front through upgrading.

Figure 10 is the schematic diagram of frame 202.When IEEE 802.11n, 802.11a and/or 802.11g equipment were arranged in the communication zone scope, this frame can be constructed according to IEEE 802.11n.In this case, frame 202 comprises: short training sequence (STS) 157, the long training sequence (LTS) 159 and 161 that meets 802.11a and/or 802.11g standard, the service data territory (SIG) 163 that meets 802.11a and/or 802.11g standard, additional long training sequence (suppl LTS) 201-203, high-speed data service section 211 and a plurality of data payload section 205-209.As shown in the figure, frame 202 comprises two frame information sections: service segment 163 and high-speed data service section 211.

Channel estimation module 120 shown in Fig. 8 is at first by determining the LTS channel estimating, generate channel estimation value, utilization and service segment corresponding channel estimation value are upgraded it subsequently, channel estimation module is determined a channel estimation value for additional LTS then, and utilizes this estimated value to upgrade the channel estimation value that the front was upgraded.High-speed data service section 211 and one or more data payload section 205-209 carry out the renewal of channel estimation value continuously.

Figure 11 is frame 204 another one schematic diagrames.Described frame can with IEEE 802.11n compatibility, be used in the communication range that contains 802.11n, 802.11a, 802.11b and/or 802.11g equipment.In this embodiment, frame 204 comprises: a short training sequence (STS) 157, traditional long training sequence (LTS) 159﹠amp; 161,163, MAC of traditional services section (SIG) divide section 213, additional long training sequence (suppl LTS) 201-203, high-speed data service section 211 and a plurality of data payload section 205-209.Channel estimation module 120 among Fig. 8 utilizes the LTS channel estimation value to determine initial channel estimation value, is that each territory and/or the district in the frame 204 determines a channel estimation value then, and utilizes these channel estimation values to upgrade the channel estimation value that the front was upgraded.In diagram, the frame information district of frame 204 comprises traditional services section 163, MAC subregion 213 and high-speed data service section 211.

Figure 12 A is the data segment schematic diagram of frame 221.Described frame can be handled by the baseband processing module among Fig. 7 and Fig. 8.Frame 221 comprises: 223, two channels of a short training sequence (STS) 157, protections time slot (GI) are intercepted (CS) 245 and 247 and signal segments (SIG) 163.In one embodiment, the cycle of frame 221 is 20 milliseconds (μ s), and wherein STS takies 4 μ s, and GI takies 1.6 μ s, and each CS takies 3.2 μ s, and signal segment takies 4 μ s.In the STS section, each symbol takies 0.8 μ s.

STS157 comprises ten Short Training symbol (s ₁-s ₁₀) 225-245.The channel of frame 221 intercepts 245 and 247, and (such as, the long training symbol among the IEEE 802.11a) satisfies following two standards:

1. tradition (802.11a/g) terminal can utilize it that the signaling section is decoded, and obtains frame length so that clear channel assessment (CCA) (CCA) parameter to be set.

2. 802.11n terminal of future generation can utilize it to carry out the estimation of (part) mimo channel.

Satisfying under the situation of this standard, channel estimation errors is reduced to a given average minimum, this sequence be high energy efficiency.For the signaling section that does not have in the conventional terminal to change,, existing long training and signaling symbols are carried out linearity increase the weight of in the importation of transmitter antenna; For the decoding of conventional terminal, the same retry that adds offers preceding two long training symbols and traditional signaling message territory.

Figure 12 B is the signal mode block diagram with frame format shown in Figure 12 A that receives.As shown in the figure, received signal (X _k) 255 comprise that transmission channel intercepts signal (S _k) 253, channel estimating (H _k) 251 and noise matrix (N _k) 257.Especially, received signal X _k=S _k ^*H _k+ N _k, S wherein _k ^*, H _k, N _kIt all is matrix.In a specific embodiment, channel estimating H _k251 and transmission channel intercept signal S _k253 have following form:

X _k＝S _k·H _k+N _k

From the sort signal form as can be seen, force zero (ZF) mimo channel to estimate and can be calculated as follows:

${\hat{H}}_k={(S_k^H\&CenterDot;S_k)}^{-1}\&CenterDot;S_k^H\&CenterDot;X_k=\frac{1}{M}\&CenterDot;S_k^H\&CenterDot;X_k$

After determining long training symbol sequence, S _kThe result be real number times unit matrix.In this case, be calculated as follows the minimum average B configuration variance (MMSE) of channel estimating:

${\hat{H}}_k={(S_k^H\&CenterDot;S_k+{\mathrm{\&sigma;}}_{\mathrm{\&eta;}}^2\&CenterDot;I)}^{-1}\&CenterDot;S_k^H\&CenterDot;X_k=\mathrm{\&rho;}\&CenterDot;S_k^H\&CenterDot;X_k$

$\mathrm{\&rho;}=\frac{1}{M+{\mathrm{\&sigma;}}_{\mathrm{\&eta;}}^2}$

Simplify when calculating, nk is made as independent same distribution (i.i.d.) gaussian variable, is selected as to carry out " good long training is selected ".S is noted that owing to generally through conscientiously selecting, in fact need not utilize MMSE to replace forcing zero (ZF) to carry out sequencal estimation.

Figure 13 is the transmission schematic diagrames of a plurality of header 261-265 in a plurality of antennas (TX 1 to TX M), the baseband processing module shown in the compatible Fig. 7 of described antenna and Fig. 8.In one embodiment, each header 261-265 correspondence comprises: 267,277,287, one first channels of a carrier detect (CD) section are intercepted (CS M, 1) 269,279,289,271,281,291 and L-1 of a signal segment (SIG) residue channel intercept (CS, M, L).In this embodiment, channel detecting CD267,277,287, first channel intercept 269,279,289 and signal segment 271,281,291 can distinguish a corresponding short training sequence, long training sequence and a conventional wireless protocols (as IEEE 802.11a, b and/or g) signal segment.

According to method provided by the present invention, the energy of header is transferred to all signals or nearly all signal, all antennas or nearly all antenna and all L from IEEE 802.11n terminal or access point and intercepts sequence.When L=M, the energy that sends from each antenna of M antenna between each L listen period is 2s ²/ M.When L=M, the gross energy of channel estimate matrix is 2Ms ²Therefore, no matter when, the M of energy doubly when total transmission of power transmitted for a signal is only arranged.

Figure 14 has the transmission mode schematic diagram of detecing form shown in Figure 12 A.Concerning this transformat, in order to satisfy the requirement of back compatible and channel estimating of future generation, should select W like this, make W and W ^-1Be easy to realize.In addition, any from MIMO (next generation), through the wave beam of [w11...w1M] matrix operation, can be received by the fine equipment of traditional 802.11a/g.(any beam forming issues fromMIMO transmitters(next generation)by[w11...w1M]should be well-received bylegacy 802.11a/g device.)

In this embodiment, channel is intercepted (S _k) 253 multiply by a plurality of weighting factor (W _{K, m}) 68-72, described k respective channels is intercepted number, and excursion is 1-1, the number of the corresponding transmitting antenna 82-86 of m.By transmitter 68-72, will intercept signal results through the channel that increases the weight of and be converted to the RF signal, by antenna 82-86 the RF signal is launched then.In one embodiment, the form of weighting factor matrix is as follows:

In all transmission courses, may form zero signal.These zero signals may be compensated by selecting to increase the weight of sequence, and become a Beam-former, cause these zero signals to be propagated towards concrete direction.For example, if vector matrix w1=[1 1] (the wherein delegation of described first front slide matrix is used for 2 TX situations), zero signal will be propagated along-90 ° of directions with+90 °, like this, compare with other traditional wlan device list input receivers, the signal on certain direction incurs loss.

The invention provides a kind of different complicated emphasis method, on M-1 transmitting antenna, this emphasis method is offered each subcarrier.Like this, on each subcarrier, form a kind of different form of beams, and reached the purpose that on the poorest direction, reduces energy and capacitance loss.

Figure 15 is the header generation type schematic diagram of frame format among Figure 12 A, and this header is usually used for MIMO transmitter of future generation, in the MIMO transmitter of future generation with double antenna.As shown in the figure, two headers, corresponding two active antennas.First header 311; by first antenna transmission, comprising: two protection (GI2) 313, one first channels at interval intercept that (CS 0; 0) 315; a second channel is intercepted (CS 0,1) 317, one protections (GI) 319 at interval; a signal segment (SIG) 321; another protection is (GI) at interval) 323, and the 3rd channel is intercepted (CS 0,2) 325.Second header 327; by second antenna transmission, comprising: two protection (GI2) 329, one first channels at interval intercept that (CS 1; 0) 331; a second channel is intercepted (CS 1,1) 333, one protections (GI) 335 at interval; a signal segment (SIG) 337; another protection is (GI) at interval) 339, and the 3rd channel is intercepted (CS 1,2) 341.

In this embodiment, channel is intercepted available following formula calculating:

s ₀₁＝s ₀₀

${\mathrm{<figure-callout\; id="10"\; label="s"\; filenames="A20051006740400391.png,A20051006740400571.png"\; state="\{\{state\}\}">s</figure-callout>}}_{10,k}={-s}_{00,k}\&CenterDot;e^{i\&CenterDot;{\mathrm{\&theta;}}_k}$

s ₁₁＝s ₁₀

s ₀₂＝s ₀₀

${\mathrm{<figure-callout\; id="12"\; label="s"\; filenames="A20051006740400391.png"\; state="\{\{state\}\}">s</figure-callout>}}_{12,k}=s_{00,k}\&CenterDot;e^{{i\&CenterDot;\mathrm{\&theta;}}_k}$

$S_k=\left[\begin{array}{cc}{s}_{10,k}& s_{11,k}\\ s_{20,k}& s_{21,k}\end{array}\right]{=s}_{00,k}\&CenterDot;\left[\begin{array}{cc}1& -1\\ 1& 1\end{array}\right]\&CenterDot;\left[\begin{array}{cc}1& 0\\ 0& e^{i\&CenterDot;{\mathrm{\&theta;}}_k}\end{array}\right]=\left[\begin{array}{cc}{s}_{00,k}& -s_{00,k}\&CenterDot;e^{i\&CenterDot;{\mathrm{\&theta;}}_k}\\ s_{00,k}& s_{00,k}\&CenterDot;e^{i\&CenterDot;{\mathrm{\&theta;}}_k}\end{array}\right]$

From the data mode of these channel detections, can draw the weighting factor of following form:

Channel is intercepted the number of the first digit respective antenna of leftover bits and pieces, the number of the corresponding symbol of second digit, the number that the k respective channels is intercepted.For example, S _{10, k}Corresponding first symbol by first antenna transmission, is used for k channel and intercepts.

Each subcarrier is in order to obtain different beams form, θ _kComputational methods as follows:

${\mathrm{\&theta;}}_k=\mathrm{\&pi;}\&CenterDot;k/6,k=-\frac{{\mathrm{<figure-callout\; id="2"\; label="N\; subcarriers"\; filenames="A20051006740400472.png,A20051006740400481.png"\; state="\{\{state\}\}">N</figure-callout>}}_{\mathrm{subcarriers}}}{2}\&CenterDot;\&CenterDot;\frac{{\mathrm{<figure-callout\; id="2"\; label="N\; subcarriers"\; filenames="A20051006740400472.png,A20051006740400481.png"\; state="\{\{state\}\}">N</figure-callout>}}_{\mathrm{subcarriers}}}{2}$

Figure 16 is the header mode schematic diagram with Figure 12 A frame format, and this header is used for the MIMO transmitter of future generation of triantennary.As shown in FIG., three headers, corresponding three active antennas.First preamble is true 351, by first antenna transmission, comprising: two protection are (GI2) 353 at interval; one first channel is intercepted (CS 0,0) 355, one second channels and is intercepted that (CS 0; 1) 357, one protection interval (GI) 359, one signal segments (SIG) 361; a protection interval (GI)) 363; one the 3rd channel is intercepted (CS 0,2) 365, one the 3rd protections (GI) 367 at interval; and one the 4th channel is intercepted (CS 0,3) 369.Second header 371 by second antenna transmission, comprising: two protections interval (GI2) 373; one first channel is intercepted (CS 1,0) 375, one second channels and is intercepted that (CS 1; 1) 377, one protection interval (GI) 379, one signal segments (SIG) 381; a protection interval (GI)) 383; one the 3rd channel is intercepted (CS 1,2) 385, one the 3rd protections (GI) 387 at interval; and one the 4th channel is intercepted (CS 0,3) 389.The 3rd header 391 by the 3rd antenna transmission, comprising: two protections interval (GI2) 393; one first channel is intercepted (CS 2,0) 395, one second channels and is intercepted that (CS 2; 1) 397, one protection interval (GI) 399, one signal segments (SIG) 401; a protection interval (GI)) 403; one the 3rd channel is intercepted (CS 2,2) 405, one the 3rd protections (GI) 407 at interval; and one the 4th channel is intercepted (CS 2,3) 409.

Different channels is intercepted, implement different weighting factor matrixes, computing formula is as follows:

$S_k=\left[\begin{array}{ccc}{s}_{10,k}& s_{11,k}& s_{12,k}\\ s_{20,k}& s_{21,k}& s_{22,k}\\ s_{30,k}& s_{31,k}& s_{32,k}\end{array}\right]=\left[\begin{array}{ccc}{s}_{00,k}& s_{00,k}\&CenterDot;e^{i\&CenterDot;{\mathrm{\&theta;}}_k}& s_{00,k}\&CenterDot;e^{i\&CenterDot;{\mathrm{\&phi;}}_k}\\ s_{00,k}& s_{00,k}\&CenterDot;e^{i\&CenterDot;({\mathrm{\&theta;}}_k-\frac{4\&CenterDot;\mathrm{\&pi;}}{3})}& s_{00,k}\&CenterDot;e^{i\&CenterDot;\left({\mathrm{\&phi;}}_k-\frac{2\&CenterDot;\mathrm{\&pi;}}{3}\right)}\\ s_{00,k}& s_{00,k}\&CenterDot;e^{i\&CenterDot;({\mathrm{\&theta;}}_k-\frac{2\&CenterDot;\mathrm{\&pi;}}{3})}& s_{00,k}\&CenterDot;e^{i\&CenterDot;\left({{\mathrm{\&phi;}}_k-}_{}\frac{4\&CenterDot;\mathrm{\&pi;}}{3}\right)}\end{array}\right]$

Each subcarrier is in order to obtain different form of beams, θ _kComputational methods as follows:

θ _k＝π·k/6

φ _k＝π·(k+4)/6

Figure 17 has the header mode schematic diagram of Figure 12 A frame format, and this header is used for the MIMO transmitter of future generation of four antennas.As shown in FIG., four preambles, corresponding four active antennas.First preamble 411; by first antenna transmission; comprise: two protections interval (GI2) 413; one first channel is intercepted (CS 0,0) 415, one second channels and is intercepted that (CS 0; 1) 417; 421, one protections of protection interval (GI) 419, one signal segments (SIG) are (GI) at interval) 423; one the 3rd channel intercepts that (CS 0; 2) 425, one the 3rd protections at interval (GI) 427, one the 4th channels intercept that (CS 0; 3) 429; protection interval (GI) 431, and one the 5th channel is intercepted (CS0,4) 435.Second header 441; by second antenna transmission; comprise: two protections interval (GI2) 443; one first channel is intercepted (CS 1,0) 445, one second channels and is intercepted that (CS 1; 1) 447; 451, one protections of protection interval (GI) 449, one signal segments (SIG) are (GI) 453 at interval; one the 3rd channel intercepts that (CS 1; 2) 455, one the 3rd protections at interval (GI) 457, one the 4th channels intercept that (CS 1; 3) 459; protection interval (GI) 461, and one the 5th channel is intercepted (CS 1,4) 465.The 3rd header 471; by the 3rd antenna transmission; comprise: two protections interval (GI2) 473; one first channel is intercepted (CS 2,0) 475, one second channels and is intercepted that (CS 2; 1) 477; 481, one protections of protection interval (GI) 479, one signal segments (SIG) are (GI) 483 at interval; one the 3rd channel intercepts that (CS 2; 2) 485, one the 3rd protections at interval (GI) 487, one the 4th channels intercept that (CS 2; 3) 489; protection interval (GI) 491, and one the 5th channel is intercepted (CS 2,4) 495.The 4th header 501; by the 4th antenna transmission; comprise: two protections interval (GI2) 503; one first channel is intercepted (CS 3,0) 505, one second channels and is intercepted that (CS 3; 1) 507; 511, one protections of protection interval (GI) 509, one signal segments (SIG) are (GI) 513 at interval; one the 3rd channel intercepts that (CS 3; 2) 515, one the 3rd protections at interval (GI) 517, one the 4th channels intercept that (CS 3; 3) 519; protection interval (GI) 521, and one the 5th channel is intercepted (CS 3,4) 525.

Embodiment to as Figure 17 has:

θ _k＝π·k/6

φ _k＝π·(k+2)/6

ψ _k＝π·(k+4)/6

Under the mode of operation of Figure 15-17, θ _k, φ _kAnd ψ _kBe set on each subcarrier, to constitute the value of different beams form.Because transmitted more energy, so 802.11n equipment of future generation can be determined better channel estimating.In addition, utilize the sort signal form, receiver of future generation can simply be forced zero (ZF) or MMSE channel estimating.

This channel estimation works can realize by two antennas, triantennary and four antenna communication devices being provided following matrix form respectively.The matrix form of each antenna correspondence is:

$W_T=\left[\begin{array}{cc}+1& -1\\ +1& +1\end{array}\right]\&DoubleRightArrow;W_T^{-1}=\frac{1}{2}\left[\begin{array}{cc}+1& +1\\ -1& +1\end{array}\right]$

$W_T=\left(\begin{array}{ccc}1& 1& 1\\ 1& \frac{-1-i\&CenterDot;\sqrt{3}}{2}& \frac{-1+i\&CenterDot;\sqrt{3}}{2}\\ 1& \frac{-1+i\&CenterDot;\sqrt{3}}{2}& \frac{-1-i\&CenterDot;\sqrt{3}}{2}\end{array}\right)\&DoubleRightArrow;W_T^{-1}=\frac{1}{3}\&CenterDot;\left(\begin{array}{ccc}1& 1& 1\\ 1& \frac{-1+i\&CenterDot;\sqrt{3}}{2}& \frac{-1-i\&CenterDot;\sqrt{3}}{2}\\ 1& \frac{-1-i\&CenterDot;\sqrt{3}}{2}& \frac{-1+i\&CenterDot;\sqrt{3}}{2}\end{array}\right)$

$W_T=\left[\begin{array}{cccc}-1& +1& +1& +1\\ +1& -1& +1& +1\\ +1& +1& -1& +1\\ +1& +1& +1& -1\end{array}\right]\&DoubleRightArrow;W_T^{-1}=\frac{1}{4}\left[\begin{array}{cccc}-1& +1& +1& +1\\ +1& -1& +1& +1\\ +1& +1& -1& +1\\ +1& +1& +1& -1\end{array}\right]$

Utilize these technology, in first embodiment, the knowledge that can form coefficient in conjunction with the wave beam of each subcarrier of front is estimated channel, so these coefficients just do not need to offer remaining transmission symbol.The advantage of the present embodiment is not need extra multiplying at transmitter terminal, so the LTRN sequence can be found by tabulation simply.

Second embodiment do not need in conjunction with the wave beam formation coefficient of each subcarrier channel to be estimated.In this embodiment, this coefficient is provided for all the other transmission symbols.The advantage of this embodiment is to have simplified receiver channel estimation (multiplying still less), but has increased the multiplying of transmitter.

To first embodiment, operational equation following (utilize the symbolic representation of front, and establish L=M):

${\hat{H}}_k=\frac{1}{M}\&CenterDot;s_{00,k}^{*}\&CenterDot;W_{B,k}^H\&CenterDot;W_T^H\&CenterDot;X_k$

$W_{B,k}=\mathrm{diag}\left(\left[\begin{array}{cccc}1& e^{\frac{i\&CenterDot;\mathrm{\&pi;}\&CenterDot;I_1}{6}}& \&CenterDot;\&CenterDot;\&CenterDot;& e^{\frac{{i\&CenterDot;\mathrm{\&pi;}\&CenterDot;I}_{M-1}}{6}}\end{array}\right]\right)$

To second embodiment, operational equation following (utilize the symbolic representation of front, and establish L=M):

${\hat{H}}_k=\frac{1}{M}{\&CenterDot;s_{00,k}^{*}\&CenterDot;W}_T^H\&CenterDot;X_k$

By whole length-M sequence is carried out p repetitive operation, can further improve the accuracy of channel estimating.Just can reach the purpose that improves precision by simple average calculating operation, the expense of the active transmitter of describing among its expense and the independent slide10 is identical, but performance wants high a lot.

For the header of back compatible, wherein the number of long training symbol is M+1, and longer sequence has p*M+1 long training symbol.P identical M symbolic blocks arranged, and first and second symbols of each antenna are identical.

Figure 18 is the mode block diagram that tradition and next generation wlan apparatus interprets are included in information in the frame head, and described frame is back compatible.In order to reduce the complexity that receiver calculates, the configuration of transmitting antenna and header 531 need be encoded at traditional signaling message section 533, another is, calculate 4 different channel estimating by receiver, select antenna/header parameter configuration 535, obtain a parity check bit coupling and unique legal value in signaling 2 (MIMO expansion).

One aspect of the present invention if be provided with the reservation position in the signaling section, utilizes " MIMO decoding " 539 pairs of speed positions 537 to decipher again.Concerning the MIMO receiver, this speed is defined as undetermined, and actual speed rate is just no longer represented in the speed position, but in conjunction with length field and TX antenna/preamble configuration, represents a virtual speed, the length of frame in the unique definite symbol of described length section.

For example, under the speed of 54Mbps, 27 possibility byte numbers are arranged in length section, generate the identical frame period in symbol, these 27 kinds possibilities can be to TX antenna/header configuration codes.In the table 1 below, three kinds of coded systems have been represented.Be noted that we can utilize the unique definite all length of " 6Mbps " speed and TX antenna/preamble configuration simply.In this case, keep the position, just no longer use other rate code if be provided with.Unique shortcoming is the coding selective power of having lost other preambles.

The decoding of table 1-rate domain

The speed position	802.11a decoding (keeping position=0)	MIMO decoding (keeping position=1)
			1101	6Mbps	Length mode 3=1=＞2TX antenna

		Length mode 3=2=＞3TX antenna length mode 3=3=＞4TX antenna
			1111	9Mbps	N/A
0101	12Mbps	Length pattern 6=1=＞2TX antenna length pattern 6=2=＞3TX antenna length pattern 6=3=＞4TX antenna
			0111	18Mbps	Length pattern 9=1=＞2TX antenna length pattern 9=2=＞3TX antenna length pattern 9=3=＞4TX antenna
1001	24Mbps	Length pattern				12=1=＞2TX antenna length pattern 12=2=＞3TX antenna length pattern 12=3=＞4TX antenna
			1011	36Mbps	Length pattern		18=1=＞2TX antenna length pattern 18=2=＞3TX antenna length pattern 18=3=＞4TX antenna
0001	48Mbps	Length pattern				24=1=＞2TX antenna length pattern 24=2=＞3TX antenna length pattern 24=3=＞4TX antenna
			0011	54Mbps	Length pattern 27=1=＞2TX antenna length pattern 27=2=＞3TX antenna length pattern 27=3=＞4TX antenna

That shown in Figure 19 is current general IEEE 802.11a, frequency characteristics 541 and a plurality of frequency characteristics 543,545,547 according to MIMO signal shielding of future generation of the present invention of the different spectral shielding of b and g.The requirement of interface of future generation may be protected an effective data rate, and this effective data rate requires to have the throughput of 100Mbps in the channel of 20MHz, and certainly, lower data rate can provide equipment room long propagation distance.For example, among the figure is the trunnion axis of unit with MHz, and expression is the side-play amount at center with 20MHz; Vertical axis is a unit with decibel (dB).In this example, spectrum mask 543 is frequency characteristicss of each passage of 20MHz channel, and this channel is selected 48 and is used to carry data from 64 subcarriers; Spectrum mask 545 is frequency characteristicss of each passage of 20MHz channel, and this channel is chosen 52 and is used to carry data from 64 subcarriers; Spectrum mask 547 is frequency characteristicss of each passage of 20MHz channel, and this channel is chosen 54 and is used to carry data from 64 subcarriers.

Under the throughput of 100Mbps, 130Mbps is peculiar (typical case) requirement of service equipment physical layer.Other requirements may comprise: concrete (special) frame format (as the frame of 4096 bytes) comprises the characteristic (as RTS/CTS) that the equipment room conflict is avoided in several frames (as a pulse 10 frames being arranged, 802.11e TXOP pulse) and support in the pulse.In order to satisfy these requirements, designed MIMO equipment.

Concerning MIMO equipment/system, also need to possess other characteristic with two TX passages.Such as, system need possess following a few specific character:

The MIMO of 2 TX passages;

48 subcarrier *, 2 tunnel/4.0us=24Msym/s (character rate: million symbol rate per seconds)

130/24=5.416 position/symbol

64QAM-0.9 rate code

128QAM-0.7737 rate code

256QAM-0.677 rate code

If possible, add carrier wave at last

The change of pilot subcarrier between the different TX streams

Each of these characteristics is in conjunction with the requirement of all satisfying system of future generation.These are in conjunction with may also possessing following properties:

Select the big cluster of 1#-

50 subcarriers excite each stream (each stream have 2 pilot frequency carrier waves alternative)

In passage 1:(-21 ,-7), (21,7), (21,21), (7,7), (7,21), (7,21)

In passage 2:(7,21), (7,21), (21,21), (21,7), (21 ,-7)

·128QAM

0.742-0.75 code rate

Select the 2#-high rate codes

52 subcarriers excite each stream (each stream have 2 pilot frequency carrier waves alternative+2 additional signal at bins+/-27)

·64QAM

5/6 code rate

Select the short cyclic prefix of 3#-

Each stream has 52 data subcarriers

Reduce by half cyclic prefix (symbol of cyclic prefix-3.6us of 0.4us)

·64QAM

3/4 code rate

In the mimo system of 2 antennas, under the prerequisite that meets the demands, each combination all has its merits and demerits.Compare with traditional IEEE 802.11a/g system, the next generation wlan system has MIMO signal format, has both used less cluster and lower code rate that long transmission range, suitable or bigger data rate still can be provided.For example: one 2 by 2MIMO system, utilize the channel of 40MHz, can support 27 and the data rate of 54Mbps.In the course of work of reality, these systems of future generation all have superiority than conventional I EEE 802.11a/g system.And 4 by 4MIMO systems had both made and had utilized and the code rate of conventional I EEE 802.11a/g system compatible, also can support higher data rate.Especially, in the 20MHz channel, when 4 by, 4 systems utilize 3/4 code rate, (equate), can support the data rate of 192Mbps with the code rate of IEEE802.11a/g.In the channel of 40MHz, utilize same code rate, 4 by, 4 systems can support the data rate of 486Mbps.

Concerning the those skilled in the art in present technique field, be readily appreciated that " fully " and " approx " these two terms that to use here, their corresponding industrial tolerances.The scope of this industrial tolerance is from less than 1% to 20%, handles with element price, integrated circuit that drift, temperature are floated, the trailing edge of time is relevant with factors such as rising edge, temperature noises, but is not limited only to this Several Factors.Concerning the those skilled in the art in present technique field, the term that also easy understanding may be used here " can be operatively connected (coupling) ", comprise direct coupling and indirect coupling, described indirect coupling is meant the coupling by another one element, parts, circuit or module.Middle parts, element, circuit or module do not change the information that signal carries, but may adjust its electric current, voltage and/or power level.Concerning the those skilled in the art in present technique field, also easily " the reasoning coupling " that may use here of understanding (just element is by the coupling of reasoning and another element), comprise the direct and indirect coupling between two elements, the same with the mode of " but operational coupled ".Concerning the those skilled in the art in present technique field, it is also understood that " rationally relatively " that may use here, its expression provides a desired relationship when comparing between two or more elements, between the product, between the signal etc.For example, when our expected relationship is a signal 1 when having bigger magnitude than signal 2, the magnitude of or signal 2 bigger than the magnitude of signal 2 in the magnitude of signal 1 than the little situation of the magnitude of signal 1 under, promptly reached the purpose of satisfied comparison.

The argumentation of front provides a kind of method and apparatus that upgrades channel estimating based on frame payload, concerning the those skilled in the art in present technique field, under the prerequisite that does not exceed the claim scope, be easy to from top disclosed content, expect other embodiment.

Claims (10)

1, a kind of in multiple-input and multiple-output (MIMO) wireless lan (wlan) the method for transmitting high speed data, it is characterized in that, comprising:

Determine a message transmission rate;

When described message transmission rate is between first data rate and second data rate, start two transmission channels;

To described two transmission channels each, determine at least one in the following:

Level of constellation (level of constellation);

Number of data subcarriers;

Rate code; And

Cyclic prefix duration.

2, method according to claim 1 is characterized in that, in the step of two transmission channels of described startup, comprising:

Activate two antennas that are used for the 20MHz channel.

3, method according to claim 1 is characterized in that, described level of constellation comprises at least one in the following:

64 quadrature amplitude modulation (QAM);

128QAM; With

256QAM。

4, method according to claim 3 is characterized in that, when described level of constellation is 64QAM, comprises at least one in the following in the described specified data number of sub purpose step:

From 64 subcarriers, select 52 and be used to transmit data; With

From 64 subcarriers, select 54 and be used to transmit data.

5, a kind of support high speed data rate WLAN method for communicating is characterized in that, comprising:

Determine a bandwidth of operation;

Determine required data throughput;

Select a number of antennas of using with multiple-input and multiple-output (MIMO) baseband signal form;

Select a cluster; And

According to described bandwidth of operation, number of antennas and MIMO WLAN transceiver of cluster control, to satisfy required data throughput.

6, method according to claim 5 is characterized in that:

Further comprise and determine a work code rate; And

Described MIMO WLAN transceiver also comes work according to described work code rate.

7, a kind of transmitter is characterized in that, comprising:

Baseband processing module; And

A plurality of radio frequencies (RF) transmitter, wherein, described processing module is used for:

Determine a message transmission rate;

When described message transmission rate is between first data rate and second data rate, start two RF transmitters in described a plurality of RF transmitter;

For described two RF transmitters each, determine at least one in the following:

Level of constellation;

Number of data subcarriers;

Rate code; And

Cyclic prefix duration.

8, transmitter according to claim 7 is characterized in that, described baseband processing module is to start described two RF transmitters in described a plurality of RF transmitter in the following way:

Activation is used for described two RF transmitters of 20MHz channel.

9, a kind of transmitter is characterized in that, comprising:

Baseband processing module; With

A plurality of radio frequencies (RF) transmitter, wherein, described processing module is used for:

Determine a bandwidth of operation;

Determine required data throughput;

From described a plurality of radio frequency sending sets, select a RF transmitter number that uses with multiple-input and multiple-output (MIMO) baseband signal form, with the RF transmitter that obtains selecting;

Select a cluster; And

Control described selected RF transmitter according to described bandwidth of operation and cluster, to satisfy required data throughput.

10, transmitter according to claim 9 is characterized in that, described baseband processing module also is used for:

Determine a work code rate; And

Described selected RF transmitter also comes work according to described work code rate.

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