CN102790742A - OFDM-based data transmission method and system - Google Patents

OFDM-based data transmission method and system Download PDF

Info

Publication number
CN102790742A
CN102790742A CN2011102302695A CN201110230269A CN102790742A CN 102790742 A CN102790742 A CN 102790742A CN 2011102302695 A CN2011102302695 A CN 2011102302695A CN 201110230269 A CN201110230269 A CN 201110230269A CN 102790742 A CN102790742 A CN 102790742A
Authority
CN
China
Prior art keywords
band
basic sub
data
sub
website
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Pending
Application number
CN2011102302695A
Other languages
Chinese (zh)
Inventor
曾勇波
雷俊
王竞
姚惠娟
闫志刚
鲍东山
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Beijing Nufront Mobile Multimedia Technology Co Ltd
Original Assignee
Beijing Nufront Wireless Technology Co Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Beijing Nufront Wireless Technology Co Ltd filed Critical Beijing Nufront Wireless Technology Co Ltd
Priority to CN2011102302695A priority Critical patent/CN102790742A/en
Priority to CN201210057448.8A priority patent/CN103227765A/en
Priority to CN201280012991.4A priority patent/CN103477598B/en
Priority to PCT/CN2012/072872 priority patent/WO2012130088A1/en
Publication of CN102790742A publication Critical patent/CN102790742A/en
Pending legal-status Critical Current

Links

Images

Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L27/00—Modulated-carrier systems
    • H04L27/26—Systems using multi-frequency codes
    • H04L27/2601—Multicarrier modulation systems
    • H04L27/2626—Arrangements specific to the transmitter only
    • H04L27/2627—Modulators
    • H04L27/2634—Inverse fast Fourier transform [IFFT] or inverse discrete Fourier transform [IDFT] modulators in combination with other circuits for modulation
    • H04L27/2636—Inverse fast Fourier transform [IFFT] or inverse discrete Fourier transform [IDFT] modulators in combination with other circuits for modulation with FFT or DFT modulators, e.g. standard single-carrier frequency-division multiple access [SC-FDMA] transmitter or DFT spread orthogonal frequency division multiplexing [DFT-SOFDM]
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L5/00—Arrangements affording multiple use of the transmission path
    • H04L5/003—Arrangements for allocating sub-channels of the transmission path
    • H04L5/0037—Inter-user or inter-terminal allocation

Landscapes

  • Engineering & Computer Science (AREA)
  • Signal Processing (AREA)
  • Computer Networks & Wireless Communication (AREA)
  • Physics & Mathematics (AREA)
  • Discrete Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Mathematical Physics (AREA)
  • Mobile Radio Communication Systems (AREA)

Abstract

The invention discloses an OFDM (Orthogonal Frequency Division Multiplexing) data transmission method, which is used for transmitting uplink data in a short or medium distance in a wireless communication system and dividing an available band of the system into N basic sub-bands in advance. The method comprises the following steps: a transmitting station occupies M basic sub-bands and modulates data to the M basic sub-bands to transmit the data; and a receiving station receives one or more data from the transmitting station within the range of the N basic sub-bands, where M is less than or equal to N, and both M and N are positive integer. The invention further provides an OFDM-based data transmission system. By the combination of the OFDM technology and the sub-bands, different bandwidth configurations in the transmitting station and the receiving station of the wireless communication system are allowed; the transmitting station can be in a low configuration to reduce the hardware cost, while the receiving station can in a high configuration to improve the efficiency, spectral efficiency, throughput rate and the like and further implement simultaneous communication between an access point and a plurality of user stations.

Description

A kind of data transmission method and system based on OFDM
It is 2011.3.25 that the application requires the applying date, and application number is 201110074380.X, and denomination of invention is a kind of based on the data transmission method of OFDM and the priority in first to file of system, should all embody in this application at the full content of first to file.
Technical field
The present invention relates to wireless communication technology field, specifically, relate to a kind of data transmission method and system based on OFDM.
Background technology
In WLAN WLAN technology based on 802.11 series standards; Insert (CSMA through carrier sense multiple; Carrier Sense Multiple Access) realizes multi-user's transmission; Be that a plurality of site STA can not insert access point AP simultaneously, can only timesharing insert, even AP is free ideler frequency spectrum resource STA to utilize.Such as, in the system of 802.11n, AP can occupy the 40MHz bandwidth resources; And can be divided into 2 20MHz subbands; STA can only utilize whole 40MHz bandwidth or one of them 20MHz subband to communicate by letter with AP, communicates by letter with AP simultaneously but the STA of two support 20MHz bandwidth can not take one of them 20MHz subband respectively, can only communicate by letter with AP in the main channel in the different time Duan Shangyong 40MHz bandwidth; And 20MHz is from channel idle, and this has just caused the waste of frequency spectrum resource.
OFDM (OFDMA; Orthogonal Frequency Division Multiple Access) be a kind of access mode that adopts in the GSM; A plurality of portable terminals (MS) take that different subcarriers group and base station (BS) communicate simultaneously in the available bandwidth, can improve the availability of frequency spectrum.
Among the existing WLAN; Must the both adopt identical band width configuration when STA communicates by letter with AP,, adopt the bandwidth of 40MHz or the bandwidth of employing 20MHz when STA communicates by letter with AP such as in the system of 802.11n; If AP supports the 40MHz bandwidth in the wlan network; The STA that two 20MHz are arranged, that AP can only adopt the band width configuration of 20MHz to communicate by letter with the STA that competes the main channel resource, therefore cause the waste of 20MHz frequency spectrum resource.In the wireless local area network technology in future, AP can with bandwidth possibly reach 80MHz even more, if continue to continue to use above-mentioned band width configuration scheme, then will cause the more waste of multiple spectra resource.
In the OFDMA mechanism; Though a plurality of terminals can take different subcarriers while and base station communication; But receiving terminal and transmitting terminal need be supported same band width configuration; The FFT that is transmitting terminal inverse fast fourier transform (IFFT, Inverse Fast Fourier Transform) module and receiving terminal fast Fourier transform (FFT, Fast Fourier Transform) module counts necessary identical.The access mode of uplink orthogonal frequency division multiple access access OFDMA is to have relatively high expectations synchronously in addition.In time-domain, the signal demand of a plurality of portable terminals (MS) emission arrives base station (BS) simultaneously and just can not cause intersymbol interference and inter-user interference; In frequency domain; Because a plurality of MS carrier of transmitter crystal oscillator frequency precision are different; Also different with the deviation of BS carrier wave crystal oscillator frequency, the frequency shift (FS) of signal of each MS that therefore arrives BS is also different, and OFDM modulation itself is to the frequency deviation sensitivity; Frequency deviation ability right demodulation must be proofreaied and correct, otherwise multi-user interference can be caused from each MS signal.Therefore, in the OFDMA system, time synchronized and Frequency Synchronization are key issues, need complicated synchronized algorithm.In wireless local area network (WLAN) system, if adopt the access mode of OFDMA will increase equipment cost in order to improve spectrum efficiency.
Summary of the invention
The present invention provides a kind of data transmission method and system based on orthogonal frequency division multiplex OFDM, can realize that a plurality of emission websites communicate with receiving station simultaneously, and complexity is low, can improve the availability of frequency spectrum, system throughput.
In order to solve the problems of the technologies described above, the present invention proposes a kind of data transmission method based on OFDM, comprising:
The emission website takies M basic sub-band, modulates data on said M the basic sub-band to send;
Receiving station receives the data of sending from one or more emission website in N basic sub-band scope;
M≤N, M, N are positive integer.
Further, said method also can have following characteristics:
Said receiving station carries out frequency-region signal to the data that receive to be separated, respectively to be launched the data that website sends.
Further, said method also can have following characteristics:
Said emission website is supported the bandwidth of M basic sub-band at least;
Said receiving station is supported the bandwidth of N basic sub-band at least.
Further, said method also can have following characteristics:
The said cell site data of naming a person for a particular job are modulated on the basic sub-band of said M independent transmission on each basic sub-band respectively.
Further, said method also can have following characteristics:
Said cell site names a person for a particular job data-modulated to the frequency band of said M basic sub-band combination, on the frequency band of said combination, transmits.
Further, said method also can have following characteristics:
Said M basic sub-band is continuous basic sub-band.
Further, said method also can have following characteristics:
A plurality of emission websites can adopt the mode of space division multiplexing to share same basic sub-band.
Further, said method also can have following characteristics:
Said emission website arrives the radio frequency band of appointment through frequency spectrum shift with the data-modulated on said M the basic sub-band.
Further, said method also can have following characteristics:
Said emission website is before carrying out frequency spectrum shift, and it is that the IFFT that M*K is ordered handles that data are carried out length;
It is that the FFT that N*K is ordered handles that said receiving station carries out length to the data that in said N basic sub-band scope, receive;
Wherein, K representes the number of the subcarrier that a basic sub-band comprises.
Further, said method also can have following characteristics:
When said emission website carried out the IFFT processing, the specimen sample speed of employing was M*fs;
When said receiving station carried out the FFT processing, the specimen sample speed of employing was N*fs;
Fs representes the input specimen sample speed of the IFFT/FFT of a basic sub-band correspondence.
Further, said method also can have following characteristics:
Said emission website also carried out the moulding Filtering Processing to the data after handling through IFFT before carrying out frequency spectrum shift;
Said receiving station also carried out matched filter processing to the data that in said N basic sub-band scope, receive before carrying out the FFT processing.
Further, said method also can have following characteristics:
At each sub-frequency bands edge the protection frequency band is set, comprises:
At the two ends of said each sub-band the virtual subnet carrier wave is set.
Further, said method also can have following characteristics:
Also comprise, the protection frequency band be set, comprising at the edge of the frequency band of the basic sub-band combination of said M:
Two ends at the frequency band of said combination are provided with the virtual subnet carrier wave.
Further, said method also can have following characteristics:
The cyclic prefix CP length T of system CPSatisfy following condition:
Figure 2011102302695100002DEST_PATH_IMAGE001
Wherein
Figure 729106DEST_PATH_IMAGE002
arrives the Round Trip Time Measurement that maximum covering radius experienced that allows for signal from the emission website, be that multidiameter is expanded.
Further, said method also can have following characteristics:
The broadband of said basic sub-band is 20MHz.
Further, said method also can have following characteristics:
K=256。
Further, said method also can have following characteristics:
fs=20MHz。
Further, said method also can have following characteristics:
M=2 n, n is a natural number.
Further, said method also can have following characteristics:
N=0,1 or 2.
In order to solve the problems of the technologies described above, the present invention also proposes a kind of emission website, comprising:
Configuration module is used for the information of M the basic sub-band that the stored transmit website allows to take: M≤N, N are the number of the basic sub-band that takies of receiving station, and M, N are positive integer;
Send processing module, be used to modulate data on said M and send on the sub-band basically.
Further, above-mentioned emission website also can have following characteristics:
Said configuration module also is used for the band width configuration that the stored transmit website can be supported, it is more than or equal to the bandwidth of M basic sub-band.
Further, above-mentioned emission website also can have following characteristics:
Said transmission processing module is modulated to data respectively on said M the basic sub-band independent transmission on each basic sub-band.
Further, above-mentioned emission website also can have following characteristics:
Said transmission processing module modulates data on the frequency band of said M basic sub-band combination, on the frequency band of said combination, transmits.
Further, above-mentioned emission website also can have following characteristics:
Said M basic sub-band is continuous basic sub-band.
Further, above-mentioned emission website also can have following characteristics:
Said transmission processing module adopts the mode of space division multiplexing and other emission websites to share same basic sub-band.
Further, above-mentioned emission website also can have following characteristics:
Said transmission processing module comprises:
The frequency spectrum shift unit is used for through frequency spectrum shift the radio frequency band of the data-modulated on said M the basic sub-band to appointment.
Further, above-mentioned emission website also can have following characteristics:
Said transmission processing module also comprises:
Length is the IFFT processing unit that M*K is ordered, and is used for data are carried out outputing to said frequency spectrum shift unit after IFFT handles;
Wherein, K representes the number of the subcarrier that a basic sub-band comprises.
Further, above-mentioned emission website also can have following characteristics:
The input specimen sample speed of said IFFT processing unit is M*fs;
Fs representes the input specimen sample speed of the IFFT/FFT of a basic sub-band correspondence.
Further, above-mentioned emission website also can have following characteristics:
Said transmission processing module also comprises:
Filter processing unit is used for after carrying out the moulding Filtering Processing through the data after the IFFT processing, exporting said frequency spectrum shift unit to.
Further, above-mentioned emission website also can have following characteristics:
Said transmission processing module comprises:
The subcarrier generation unit is provided with the virtual subnet carrier wave through the two ends at each sub-band, at said each sub-frequency bands edge the protection frequency band to be set.
Further, above-mentioned emission website also can have following characteristics:
Said transmission processing module comprises:
The subcarrier generation unit is provided with the virtual subnet carrier wave through the two ends at the frequency band of the basic sub-band combination of said M, with the two ends at the frequency band of said combination the virtual subnet carrier wave is set.
Further, above-mentioned emission website also can have following characteristics:
The broadband of said basic sub-band is 20MHz.
Further, above-mentioned emission website also can have following characteristics:
K=256。
Further, above-mentioned emission website also can have following characteristics:
fs=20MHz。
Further, above-mentioned emission website also can have following characteristics:
M=2 n, n is a natural number.
Further, above-mentioned emission website also can have following characteristics:
N=0,1 or 2.
In order to solve the problems of the technologies described above, the present invention also proposes a kind of data transmission system based on OFDM, comprising:
Aforesaid emission website;
Receiving station is used in N basic sub-band scope, receiving the data of sending from one or more emission website.
In sum; Technical scheme provided by the invention; Use based on OFDM technology and sub-band combination, allow the emission site STA in the wireless communication system with receiving station AP different band width configuration to be arranged, the emission site STA can adopt lower configuration to reduce hardware implementation cost; Receiving station AP then can adopt higher configuration to raise the efficiency: the availability of frequency spectrum, throughput etc., and can realize that a plurality of STA communicate with AP simultaneously.In addition; Having increased the protection frequency band at the edge of sub-band is virtual carrier, can avoid disturbing between sub-band, and each sub-frequency bands can do molding filtration without help; And receiving terminal only need be done the matched filtering on the whole frequency band, need not a plurality of band receiver of base and does matched filtering to different sub-bands; Expand Cyclic Prefix (CP), reduced the requirement of time synchronized.Receiving terminal baseband sample sampling rate is N a times of basic subband samples sampling rate; Guarantee an IFFT/FFT module that needs N1 to order on the basic sub-band; The IFFT/FFT module that receiving terminal is ordered with N2=N*N1, and do not need a plurality of parallel N1 point IFFT/FFT modules to come the information of each sub-frequency bands of demodulation.So both can improve the availability of frequency spectrum, system throughput, and can realize that a plurality of STA communicate with AP simultaneously, and needn't increase the cost of system and user site equipment.
Description of drawings
Fig. 1 is a kind of data transmission method flow chart based on OFDM of the embodiment of the invention;
Fig. 2 is a wireless communication system architecture sketch map in the prior art;
Fig. 3 is multi-band OFDM transmitting terminal and a receiving terminal baseband portion module frame chart in the embodiment of the invention;
Fig. 4 (a) and (b), (c) and (d) be respectively several kinds of sub-band division sketch mapes in the embodiment of the invention;
Fig. 5 (a) and 5 (b) are two kinds of sub-band division sketch mapes in addition among Fig. 4 (b).
Fig. 6 is a kind of device block diagram of launching website of the embodiment of the invention.
Embodiment
In view of deficiency of the prior art; The present invention proposes a kind of multi-user data transmission plan that is used for the short-distance and medium-distance radio communication; Employing is similar to multi-user's access way of OFDM OFDMA; Based on OFDM and corresponding synchronous mechanism; The available band of system is divided into N basic sub-band, and the bandwidth of transmitting terminal (STA) transceiver can be the frequency band of basic sub-band or sub-band combination, and receiving station (AP) transceiver bandwidth can be N basic sub-band as the case may be.Suppose; Basic sub-band is 20MHz; Receiving station (AP) transceiver bandwidth can be 20 MHz, 40 MHz, 80 MHz, promptly also can receive and dispatch the signal of the AP of 80MHz bandwidth for the STA receiver of only supporting the 20MHz bandwidth, like this; The present invention is based on the OFDM modulation technique and can realize that a plurality of STA utilize different sub-band resources to communicate by letter with AP, and reduced required Time and Frequency Synchronization requirement and the synchronization accuracy of OFDMA system.
A kind of data transmission method based on OFDM provided by the invention is used for short-distance and medium-distance wireless communication system transmitting uplink data, and the available band of system is divided into N basic sub-band, and as shown in Figure 1, this method comprises:
Step S101: the emission website takies M basic sub-band, modulates data on said M the basic sub-band to send;
Step S102: receiving station receives the data of sending from one or more emission website in N basic sub-band scope.
Wherein, M≤N, M, N are positive integer.
Afterwards, said receiving station separates through the data that receive being carried out frequency-region signal, is respectively launched the data that website sends.
Said emission website is supported the bandwidth of M basic sub-band at least; Said receiving station is supported the bandwidth of N basic sub-band at least.For example, support the STA of 80MHz bandwidth can take 20MHz, 40MHz or 80MHz transmission data.In like manner, support the AP of 80MHz bandwidth also can in 20MHz, 40MHz or 80MHz scope, receive data.
Above-mentioned M, the N parameter configuration is realized that by media access control layer (MAC) layer the value of M can be configured according to bandwidth ability and the assignable resource that STA supports by AP.The value of N is then by the needs configuration of AP according to bandwidth resources.When concrete the realization; STA sends resource request to said AP; Carry the bandwidth ability that said STA supports in the said resource request; AP is that said STA disposes basic sub-band according to bandwidth ability and the current allowable resource that said STA supports, and carries to said STA and dispose basic sub-band information to said STA through sending response message.Preferably, said emission website can send said resource request on a basic sub-band, to improve utilization ratio of transmission resources.
And the present invention mainly is intended to provide a kind of data transmission method based on OFDM, allows STA and AP to support that bandwidth ability is different, how to dispose M, and the N parameter is not this case institute focal point, so be not described in detail in this.The implementation method that different STA of bandwidth ability that the present invention allows to support and AP communicate will be detailed below.
Said emission website can be modulated to data respectively on said M the basic sub-band independent transmission on each basic sub-band.Said emission website also can modulate data on the frequency band of said M basic sub-band combination, on the frequency band of said combination, transmits.Wherein, said M basic sub-band is continuous basic sub-band.Preferably, a plurality of emission websites also can adopt the mode of space division multiplexing to share same basic sub-band.
In the data transmission method that the embodiment of the invention provides, send data, then for each emission website is provided with carrier frequency offset respectively, with the centre carrier frequency of confirming respectively to launch website as a plurality of emission websites.That is, said emission website can be through frequency spectrum shift with the radio frequency band of the data-modulated on said M the basic sub-band to appointment.Correspondingly, said receiving station receives the data of corresponding emission website on the radio frequency band of correspondence.
In the data transmission method provided by the invention, baseband portion adopts inverse fast fourier transform IFFT/ fast Fourier transform FFT to handle, and then receiving station adopts and the different FFT length of emission website:
If basic sub-band is with K point IFFT/FFT module, if the emission website takies M basic sub-band, the IFFT/FFT block length of emission website is the M*K point, and the IFFT/FFT block length of receiving station is the N*K point.That is, said emission website is before carrying out frequency spectrum shift, and it is that the IFFT that M*K is ordered handles that data are carried out length; It is that the FFT that N*K is ordered handles that said receiving station carries out length to the data that in said N basic sub-band scope, receive.Wherein, K representes the number of the subcarrier that a basic sub-band comprises.
When said emission website carried out the IFFT processing, the specimen sample speed of employing was M*fs; When said receiving station carried out the FFT processing, the specimen sample speed of employing was N*fs.Fs representes the input specimen sample speed of the IFFT/FFT of a basic sub-band correspondence.
If the emission website is supported identical bandwidth with receiving station, IFFT/FFT sub-carrier number, the sampling rate of then launching website and receiving station are all identical.
If a plurality of emission websites are arranged in the system, the bandwidth that each emission website is supported is different, and under the prerequisite that satisfies the band width configuration requirement, a plurality of emission websites can send data with band width configuration separately to receiving station in the bandwidth range of receiving station support.
Said emission website only needed the data on M the basic sub-band are carried out the moulding Filtering Processing before carrying out frequency spectrum shift.And said receiving station carried out matched filter processing to the uniform data that in said N basic sub-band scope, receives and gets final product before carrying out the FFT processing.
Preferably, the protection frequency band can be set at the sub-band edge,, reduce inter-user interference to reduce filtering requirements.The virtual subnet carrier wave can be set at the two ends of each sub-band.Preferably, also can the virtual subnet carrier wave be set at the two ends of the frequency band of said combination.
In the data transmission method that the embodiment of the invention provides, send data, the cyclic prefix CP length T of this wireless communication system is set as a plurality of emission websites CPSatisfy following condition:
Figure 990323DEST_PATH_IMAGE001
Wherein arrives the Round Trip Time Measurement that maximum covering radius experienced that allows for signal from the emission website, the expansion of
Figure 714882DEST_PATH_IMAGE003
multidiameter.
Preferably, in the embodiment of the invention, the sub-band broadband can be 20MHz; And/or M=1,2,4; And/or K=256; And/or baseband sample sampling rate fs=20MHz.
Preferably, the value of M can do, M=2 n, n is a natural number.Preferably, the value of n can be n=0,1 or 2.
  
For making principle of the present invention, characteristic and advantage clearer, describe the present invention below in conjunction with specific embodiment.
Fig. 2 is the schematic block diagram of transmitting terminal and receiving terminal, and the embodiment of the invention only relates to the part of module of base band in transmitting terminal and the receiving terminal, and therefore, the module that the present invention does not relate in information source shown in Figure 2, radio frequency, the stay of two nights and the baseband portion repeats no more at this.
At first, the whole frequency band with system is divided into N basic sub-band, each STA website use in the confession system.
In the present embodiment; The whole frequency band bandwidth of system is W=80MHz; It is divided into N=4 basic sub-band; Each basic sub-band bandwidth B=20MHz suppose that each basic sub-band can only be taken separately by an emission site STA, and a STA can use one or more basic sub-bands to transmit data to AP.STA supports 20MHz, 40MHz and 80MHz bandwidth, and AP supports 20MHz, 40MHz and 80MHz bandwidth, when AP has 80MHz bandwidth receiving ability, can receive the data of norator combinations of bands transmission simultaneously.Shown in Figure 3 is that the site STA 1～STA4 of 4 20MHz bandwidth takies the baseband portion module frame chart of different sub-bands when the AP of 80MHz bandwidth transmission data respectively.
Have 4 STA to send data to AP shown in Fig. 3, represent with STA1～STA4, it is the 20MHz bandwidth that each STA takies a basic sub-band, and X1～X4 representes the data from corresponding STA.Only show when realizing being with the OFDM transmission among Fig. 3 and the closely-related module of IFFT/FFT more; Other does not relate to does not influence a module in the complete transceiver yet, repeats no more at this such as coding, constellation point mapping, stream parsing, channel estimating, MIMO detection, decoding etc.
Sub-band division in the embodiment of the invention is shown in Fig. 4 (a).
Fig. 4 is the equivalent base band sketch map of sub-band division, for simplicity, can continue to use the negative frequency notion that the 802.11n standard is used; To positive frequency, but both in itself and indifference with the frequency spectrum shift of negative frequency.AP uses [40MHz, 40MHz] frequency range 80MHz bandwidth altogether, centre frequency f0=0.Only illustrated the situation of STA single antenna among Fig. 4, be applicable to that equally also STA and AP are that many antennas are monopolized sub-band and a plurality of STA situation through space division multiplexing shared Sub frequency band.
Fig. 4 (a) is depicted as the sketch map of 4 shared frequency bands of STA among Fig. 3, wherein, f0=0, STA1 uses [40MHz;-20MHz] frequency range, centre frequency f1=-30MHz, STA2 uses [20MHz, 0MHz] frequency range; Centre frequency f2=-10MHz, STA3 uses [0MHz, 20MHz] frequency range, centre frequency f3=10MHz; STA4 uses [20MHz, 40MHz] frequency range, centre frequency f4=30MHz.
The signal model of the sub-band division shown in Fig. 4 (a) is described below.Walk abreast and send 4 road 20MHz signals, can separate the assurance quadrature to each road signal, promptly be modulated to respectively on nonoverlapping frequency range at frequency domain.Sub-carrier number Nfft (counting of IFFT/FFT conversion), sampling interval T SAnd sample frequency f SBetween corresponding relation as shown in the formula:
Figure DEST_PATH_IMAGE005
Tu representes the duration of OFDM symbol.The baseband signal centre frequency , its subcarrier spacing does
Figure DEST_PATH_IMAGE007
The time, the sub-carrier number Nfft that adopts in the present embodiment (counting of IFFT/FFT conversion), sampling interval T SAnd sample frequency f SBetween corresponding relation as shown in table 1.
Table 1
Bandwidth B Sub-carrier number Nfft Sampling interval T S Sample frequency fs
20MHz 256 50ns 20MHz
40MHz 512 25ns 40MHz
80MHz
1024 12.5ns 80MHz
Sample frequency fs in the table 1 is minimum sampling rate, can adjust employing greater than the value shown in the table 1.
In the present embodiment, the centre frequency of 4 road signals is respectively f 1=-30MHz, f 2=-10MHz, f 3=10MHz, f 1=30MHz just in time occupies one section continuous 80MHz channel, and the sub-carrier offset value that each road signal center frequency is corresponding is respectively :-384
Figure 770005DEST_PATH_IMAGE008
,-128
Figure 355707DEST_PATH_IMAGE008
, 128
Figure DEST_PATH_IMAGE009
, 384
Figure 847868DEST_PATH_IMAGE008
With reference to Fig. 3 and Fig. 4 (a), in the present embodiment, the data of each STA are at first passed through the IFFT conversion of Nfft1=256 point (sub-carrier number); The sampling interval of baseband sample (sampling interval of IFFT module input sample point) is 50ns, passes through D/A (D/A partly comprises LPF) then, carries out frequency spectrum shift again; Centre frequency is respectively f1～f4, f1=f0-30 wherein, f2=f0-10; F3=f0+10, f4=f0+30, unit is MHz; Through being received by AP behind other resume module of base band, radio-frequency channel and the channel, the data that AP receives are at first also through the processing of radio-frequency channel and other module of base band, and the baseband sample point sampling of AP is 12.5ns at interval; The FFT conversion of ordering through Nfft2=1024 can be carried out subsequent treatment from the data that corresponding frequency band is taken out different STA.
Do not consider under the situation of time deviation, frequency departure, interference noise, suppose that the receiving terminal base band receives that the continuous signal of different carrier frequency is following:
Figure 89494DEST_PATH_IMAGE010
（1）
To signal sampling, get
Figure DEST_PATH_IMAGE011
Figure 426934DEST_PATH_IMAGE012
（2）
Receiver to the 80MHz bandwidth; N=1024;
Figure DEST_PATH_IMAGE013
, the substitution following formula gets:
Figure 634187DEST_PATH_IMAGE014
（3）
R (n) is done 1024 FFT conversion can demodulation obtain signal W, X, Y, Z.
For guaranteeing that the signal period is consistent, to the signal of different bandwidth, the sampling rate of FFT module input data is different.Under the 20MHz bandwidth, 256 FFT, the sampling period should be 50ns; And under the 80MHz bandwidth, 1024 FFT, the sampling period is 12.5ns.
In the embodiment of the invention, group of subbands supplies each website to use altogether, such as, can two sub-frequency bands synthesize a use, or the synthetic frequency band of all group of subbands uses.Sub-band combination mode in the present embodiment is shown in Fig. 4 (b), Fig. 4 (c) and Fig. 4 (d).
Fig. 4 (b) is depicted as the sub-band division signal of the shared 80MHz frequency spectrum of STA of STA and a 40MHz bandwidth of two 20MHz bandwidth, and the centre frequency of three sub-frequency bands is respectively f1=-30MHz, f2=0, f3=30MHz.In addition, Fig. 4 (b) also has two kinds of distortion, and is as shown in Figure 5.
Fig. 4 (c) is depicted as the sub-band division signal of the shared 80MHz frequency spectrum of STA of two 40MHz bandwidth, and the centre frequency of two sub-frequency bands is respectively f1=-20MHz, f2=20MHz.
The STA that Fig. 4 (d) is depicted as a 80MHz bandwidth takies the sub-band division signal of all 80MHz frequency spectrums, and the sub-band centre frequency is f1=0.
Wherein, Fig. 4 (b) is depicted as the situation of the shared 80MHz frequency spectrum of STA of STA and a 40MHz bandwidth of two 20MHz bandwidth, and frequency band distributes also convertible, specifically as shown in Figure 5.
When AP is configured to 40MHz or 80MHz bandwidth, allow in its frequency spectrum, to have idle basic sub-band or basic sub-band combination.
If the emission website is supported identical bandwidth with receiving station, IFFT/FFT sub-carrier number, the sampling rate of then launching site STA and receiving station are all identical;
If a plurality of emission websites are arranged in the system, the bandwidth that each emission website is supported is different, and under the prerequisite that satisfies the band width configuration requirement, a plurality of emission websites can send data with band width configuration separately to receiving station in the bandwidth range of receiving station support.
For example, if the system bandwidth available bandwidth is 40MHz, then AP supports 40MHz, and STA supports 20MHz or 40MHz, and AP supports that two STA transmit simultaneously.If system's available bandwidth is 20MHz, also can this frequency band be continued to divide, a part of resource in each STA service band, but the centre frequency of each STA is all identical with AP, the no longer extra frequency spectrum shift (centre frequency biasing) of doing.
The shared sub-band of each STA all has virtual subnet carrier wave separately, is arranged on the edge (two ends) of sub-band, is used for as the protection frequency band.Each STA only need do the molding filtration on its bandwidth of supporting separately, rather than the molding filtration on the whole W.And AP does the molding filtration on the whole bandwidth W, so AP can support the STA of different bandwidth configuration neatly.
In order to eliminate or to reduce to produce intersymbol interference (ISI to greatest extent; Inter-Symbol Interference) and multi-user interference, need synchronization mechanism reasonable in design in the system, specifically; Introduce Cyclic Prefix (CP; Cyclic Prefix), and the length of cyclic prefix CP changes along with transmission mode, frame structure and corresponding protocol, needs to design the length of cyclic prefix CP in the system that meets the demands.In the embodiment of the invention, the emission site STA can be confirmed a time point t according to the synchronization preamble of downlink frame when receiving the downlink frame that receiving station AP sends 0, each STA is that benchmark calculates uplink constantly with the time point of estimating separately, the CP length in the design system guarantees to have covered the Round Trip Time Measurement of the STA of furthest to AP
Figure DEST_PATH_IMAGE015
And multidiameter expansion
Figure 31670DEST_PATH_IMAGE003
, consider time synchronization error again, then the multipath signal of all STA all can arrive STA in the CP scope, is unlikely to produce intersymbol interference (ISI) and multi-user interference.
In the embodiment of the invention, send data, the cyclic prefix CP length T of this wireless communication system is set as a plurality of emission websites CPNeed satisfy following condition:
Figure 760592DEST_PATH_IMAGE016
?。
The embodiment of the invention also provides a kind of emission website, and is as shown in Figure 6, comprising:
Configuration module 61 is used for the information of M the basic sub-band that the stored transmit website allows to take: M≤N, N are the number of the basic sub-band that takies of receiving station, and M, N are positive integer; Send processing module 62, be used to modulate data on said M and send on the sub-band basically.The configuration information of the basic sub-band of said M is that receiving station is its configuration.
Preferably, said configuration module 61 also is used for the band width configuration that the stored transmit website can be supported, it is more than or equal to the bandwidth of M basic sub-band.
Preferably, said transmission processing module 62 can be modulated to data respectively on said M the basic sub-band independent transmission on each basic sub-band.
Preferably, said transmission processing module 62 also can modulate data on the frequency band of said M basic sub-band combination, on the frequency band of said combination, transmits.Preferably, said M basic sub-band is continuous basic sub-band.
Preferably, said transmission processing module 62 can also adopt the mode of space division multiplexing and other emission websites to share same basic sub-band.
Preferably, said transmission processing module 62 comprises:
Frequency spectrum shift unit 624 is used for through frequency spectrum shift the radio frequency band of the data-modulated on said M the basic sub-band to appointment.
Preferably, said transmission processing module 62 also comprises:
Length is the IFFT processing unit 622 that M*K is ordered, and is used for data are carried out outputing to said frequency spectrum shift unit 624 after IFFT handles.Wherein, K representes the number of the subcarrier that a basic sub-band comprises.
Preferably, the input specimen sample speed of said IFFT processing unit 622 is M*fs.Fs representes the input specimen sample speed of the IFFT/FFT of a basic sub-band correspondence.
Preferably, said transmission processing module 62 also comprises:
Filter processing unit 623 is used for after carrying out the moulding Filtering Processing through the data after the IFFT processing, exporting said frequency spectrum shift unit 624 to.
Preferably, said transmission processing module 62 comprises:
Subcarrier generation unit 621 can be provided with the virtual subnet carrier wave through the two ends at each sub-band, at said each sub-frequency bands edge the protection frequency band to be set.Shown in subcarrier generation unit 621, can also the virtual subnet carrier wave be set through two ends at the frequency band of the basic sub-band combination of said M, with two ends the virtual subnet carrier wave is set at the frequency band of said combination.
Preferably, the broadband of said basic sub-band is 20MHz.
Preferably, K=256.
Preferably, fs=20MHz.
Preferably, M=2n, n are natural number.Preferably, n=0,1 or 2.
  
The embodiment of the invention also provides a kind of data transmission system based on OFDM.This system can be used for the short-distance and medium-distance radio communication, and the available band of this system is divided into N basic sub-band.This system comprises: aforesaid emission website and the receiving station that is used in the basic sub-band scope of N, receiving the data of sending from one or more emission website.If a plurality of emission websites are arranged in the system, the bandwidth that each emission website is supported is different, and under the prerequisite that satisfies the band width configuration requirement, a plurality of emission websites can send data with band width configuration separately to receiving station in the bandwidth range of receiving station support.
In sum; Technical scheme provided by the invention; Use based on OFDM technology and sub-band combination, allow the emission site STA in the wireless communication system with receiving station AP different band width configuration to be arranged, the emission site STA can adopt lower configuration to reduce hardware implementation cost; Receiving station AP then can adopt higher configuration to raise the efficiency: the availability of frequency spectrum, throughput etc., and can realize that a plurality of STA communicate with AP simultaneously.In addition; Having increased the protection frequency band at the edge of sub-band is virtual carrier, can avoid disturbing between sub-band, and each sub-frequency bands can do molding filtration without help; And receiving terminal only need be done the matched filtering on the whole frequency band; Need not a plurality of band receiver of base and do matched filtering, expanded Cyclic Prefix (CP), reduce the requirement of time synchronized to different sub-bands.Receiving terminal baseband sample sampling rate is N a times of basic subband samples sampling rate; Guarantee an IFFT/FFT module that needs N1 to order on the basic sub-band; The IFFT/FFT module that receiving terminal is ordered with N2=N*N1, and do not need a plurality of parallel N1 point IFFT/FFT modules to come the information of each sub-frequency bands of demodulation.So both can improve availability of frequency spectrum system throughput, and can realize that a plurality of STA communicate with AP simultaneously, and needn't increase the cost of system and user site equipment.
Though the present invention with preferred embodiment openly as above; But it is not to be used for limiting the present invention; Any those skilled in the art are not in breaking away from essence of the present invention and scope; Can make possible change and modification, so protection scope of the present invention should be as the criterion with the scope that claim of the present invention was defined.

Claims (37)

1. data transmission method based on OFDM is characterized in that:
The emission website takies M basic sub-band, modulates data on said M the basic sub-band to send;
Receiving station receives the data of sending from one or more emission website in N basic sub-band scope;
M≤N, M, N are positive integer.
2. data transmission method as claimed in claim 1 is characterized in that, also comprises:
Said receiving station carries out frequency-region signal to the data that receive to be separated, respectively to be launched the data that website sends.
3. data transmission method as claimed in claim 1 is characterized in that:
Said emission website is supported the bandwidth of M basic sub-band at least;
Said receiving station is supported the bandwidth of N basic sub-band at least.
4. data transmission method as claimed in claim 1 is characterized in that:
The said cell site data of naming a person for a particular job are modulated on the basic sub-band of said M independent transmission on each basic sub-band respectively.
5. data transmission method as claimed in claim 1 is characterized in that:
Said cell site names a person for a particular job data-modulated to the frequency band of said M basic sub-band combination, on the frequency band of said combination, transmits.
6. data transmission method as claimed in claim 5 is characterized in that:
Said M basic sub-band is continuous basic sub-band.
7. data transmission method as claimed in claim 1 is characterized in that:
A plurality of emission websites can adopt the mode of space division multiplexing to share same basic sub-band.
8. data transmission method as claimed in claim 1 is characterized in that:
Said emission website arrives the radio frequency band of appointment through frequency spectrum shift with the data-modulated on said M the basic sub-band.
9. data transmission method as claimed in claim 8 is characterized in that:
Said emission website is before carrying out frequency spectrum shift, and it is that the IFFT that M*K is ordered handles that data are carried out length;
It is that the FFT that N*K is ordered handles that said receiving station carries out length to the data that in said N basic sub-band scope, receive;
Wherein, K representes the number of the subcarrier that a basic sub-band comprises.
10. data transmission method as claimed in claim 9 is characterized in that:
When said emission website carried out the IFFT processing, the specimen sample speed of employing was M*fs;
When said receiving station carried out the FFT processing, the specimen sample speed of employing was N*fs;
Fs representes the input specimen sample speed of the IFFT/FFT of a basic sub-band correspondence.
11. data transmission method as claimed in claim 10 is characterized in that:
Said emission website also carried out the moulding Filtering Processing to the data after handling through IFFT before carrying out frequency spectrum shift;
Said receiving station also carried out matched filter processing to the data that in said N basic sub-band scope, receive before carrying out the FFT processing.
12. data transmission method as claimed in claim 4 is characterized in that, also comprises, at each sub-frequency bands edge the protection frequency band is set, and comprising:
At the two ends of said each sub-band the virtual subnet carrier wave is set.
13. data transmission method as claimed in claim 5 is characterized in that, also comprises, at the edge of the frequency band of the basic sub-band combination of said M the protection frequency band is set, and comprising:
Two ends at the frequency band of said combination are provided with the virtual subnet carrier wave.
14. data transmission method as claimed in claim 1 is characterized in that, the cyclic prefix CP length T of system CPSatisfy following condition:
Figure DEST_PATH_IMAGE001
Wherein
Figure 933950DEST_PATH_IMAGE002
arrives the Round Trip Time Measurement that maximum covering radius experienced that allows for signal from the emission website,
Figure DEST_PATH_IMAGE003
be that multidiameter is expanded.
15., it is characterized in that the broadband of said basic sub-band is 20MHz like any one described data transmission method among the claim 1-14.
16. data transmission method as claimed in claim 15 is characterized in that, K=256.
17. data transmission method as claimed in claim 16 is characterized in that, fs=20MHz.
18., it is characterized in that M=2 like any one described data transmission method among the claim 1-17 n, n is a natural number.
19. data transmission method as claimed in claim 18 is characterized in that, n=0,1 or 2.
20. an emission website is characterized in that, comprising:
Configuration module is used for the information of M the basic sub-band that the stored transmit website allows to take: M≤N, N are the number of the basic sub-band that takies of receiving station, and M, N are positive integer;
Send processing module, be used to modulate data on said M and send on the sub-band basically.
21. emission website as claimed in claim 20 is characterized in that:
Said configuration module also is used for the band width configuration that the stored transmit website can be supported, it is more than or equal to the bandwidth of M basic sub-band.
22. emission website as claimed in claim 20 is characterized in that:
Said transmission processing module is modulated to data respectively on said M the basic sub-band independent transmission on each basic sub-band.
23. emission website as claimed in claim 20 is characterized in that:
Said transmission processing module modulates data on the frequency band of said M basic sub-band combination, on the frequency band of said combination, transmits.
24. emission website as claimed in claim 23 is characterized in that:
Said M basic sub-band is continuous basic sub-band.
25. emission website as claimed in claim 20 is characterized in that:
Said transmission processing module adopts the mode of space division multiplexing and other emission websites to share same basic sub-band.
26. emission website as claimed in claim 20 is characterized in that, said transmission processing module comprises:
The frequency spectrum shift unit is used for through frequency spectrum shift the radio frequency band of the data-modulated on said M the basic sub-band to appointment.
27. emission website as claimed in claim 26 is characterized in that, said transmission processing module also comprises:
Length is the IFFT processing unit that M*K is ordered, and is used for data are carried out outputing to said frequency spectrum shift unit after IFFT handles;
Wherein, K representes the number of the subcarrier that a basic sub-band comprises.
28. emission website as claimed in claim 27 is characterized in that:
The input specimen sample speed of said IFFT processing unit is M*fs;
Fs representes the input specimen sample speed of the IFFT/FFT of a basic sub-band correspondence.
29. emission website as claimed in claim 28 is characterized in that, said transmission processing module also comprises:
Filter processing unit is used for after carrying out the moulding Filtering Processing through the data after the IFFT processing, exporting said frequency spectrum shift unit to.
30. emission website as claimed in claim 22 is characterized in that, said transmission processing module comprises:
The subcarrier generation unit is provided with the virtual subnet carrier wave through the two ends at each sub-band, at said each sub-frequency bands edge the protection frequency band to be set.
31. emission website as claimed in claim 23 is characterized in that, said transmission processing module comprises:
The subcarrier generation unit is provided with the virtual subnet carrier wave through the two ends at the frequency band of the basic sub-band combination of said M, with the two ends at the frequency band of said combination the virtual subnet carrier wave is set.
32., it is characterized in that the broadband of said basic sub-band is 20MHz like any one described emission website among the claim 20-31.
33. emission website as claimed in claim 32 is characterized in that K=256.
34. emission website as claimed in claim 33 is characterized in that fs=20MHz.
35., it is characterized in that M=2 like any one described emission website among the claim 20-34 n, n is a natural number.
36. emission website as claimed in claim 35 is characterized in that, n=0,1 or 2.
37. the data transmission system based on OFDM is characterized in that, comprising:
Like any one described emission website among the claim 20-36;
Receiving station is used in N basic sub-band scope, receiving the data of sending from one or more emission website.
CN2011102302695A 2011-03-25 2011-08-11 OFDM-based data transmission method and system Pending CN102790742A (en)

Priority Applications (4)

Application Number Priority Date Filing Date Title
CN2011102302695A CN102790742A (en) 2011-03-25 2011-08-11 OFDM-based data transmission method and system
CN201210057448.8A CN103227765A (en) 2011-03-25 2012-03-06 Data transmission method based on orthogonal frequency division multiplexing (OFDM) and transmitting station
CN201280012991.4A CN103477598B (en) 2011-03-25 2012-03-23 A kind of data transmission method based on OFDM and transmitting website
PCT/CN2012/072872 WO2012130088A1 (en) 2011-03-25 2012-03-23 Ofdm-based data transmission method and transmission station

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
CN201110074380.X 2011-03-25
CN201110074380 2011-03-25
CN2011102302695A CN102790742A (en) 2011-03-25 2011-08-11 OFDM-based data transmission method and system

Publications (1)

Publication Number Publication Date
CN102790742A true CN102790742A (en) 2012-11-21

Family

ID=46482971

Family Applications (3)

Application Number Title Priority Date Filing Date
CN2011102302695A Pending CN102790742A (en) 2011-03-25 2011-08-11 OFDM-based data transmission method and system
CN201210057589XA Pending CN102594763A (en) 2011-03-25 2012-03-06 Method and system for transmitting data based on Orthogonal Frequency Division Multiplexing (OFDM)
CN201280012927.6A Active CN103444146B (en) 2011-03-25 2012-03-23 A kind of data transmission method and system based on OFDM

Family Applications After (2)

Application Number Title Priority Date Filing Date
CN201210057589XA Pending CN102594763A (en) 2011-03-25 2012-03-06 Method and system for transmitting data based on Orthogonal Frequency Division Multiplexing (OFDM)
CN201280012927.6A Active CN103444146B (en) 2011-03-25 2012-03-23 A kind of data transmission method and system based on OFDM

Country Status (2)

Country Link
CN (3) CN102790742A (en)
WO (1) WO2012130090A1 (en)

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2016124982A1 (en) * 2015-02-06 2016-08-11 Nokia Technologies Oy Methods and apparatus for coordination of wireless network communication
CN107666453A (en) * 2016-07-28 2018-02-06 上海诺基亚贝尔股份有限公司 Transmitter and corresponding method
WO2024078103A1 (en) * 2022-10-09 2024-04-18 华为技术有限公司 Burst optical signal transmission method and related device

Families Citing this family (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20150223246A1 (en) * 2014-02-05 2015-08-06 Qualcomm Incorporated Systems and methods for improved communication efficiency in high efficiency wireless networks
CN106063341B (en) * 2014-03-06 2019-11-05 华为技术有限公司 A kind of uplink, downlink data transmission method
US9716579B2 (en) 2014-08-19 2017-07-25 Intel IP Corporation Subcarrier allocations for operation in mixed bandwidth environments
US10314066B2 (en) * 2015-05-05 2019-06-04 Qualcomm Incorporated Techniques for protecting communications in wireless local area networks
CN105356948B (en) * 2015-09-30 2018-06-19 小米科技有限责任公司 For the method and apparatus of data transmission
CN106713180B (en) * 2015-11-18 2020-09-04 南京中兴软件有限责任公司 Hotspot device control method and device
WO2018027812A1 (en) * 2016-08-11 2018-02-15 华为技术有限公司 A data processing method and device
CN114364047A (en) 2017-06-16 2022-04-15 Lg电子株式会社 Method for performing communication by user equipment and base station and apparatus for wireless communication

Family Cites Families (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP1478148A1 (en) * 2003-05-15 2004-11-17 Siemens Aktiengesellschaft Wireless multicarrier communication method with dynamic allocation of frequency width and number of subbands
JP4775288B2 (en) * 2006-04-27 2011-09-21 ソニー株式会社 Wireless communication system, wireless communication apparatus, and wireless communication method
CN101145828B (en) * 2006-09-11 2012-01-25 华为技术有限公司 A data transmission method and device based on minimum coverage
CN101166080B (en) * 2006-10-20 2010-11-24 北京新岸线无线技术有限公司 Method and system for realizing high data rate ODFM WLAN
CN101572683A (en) * 2008-04-30 2009-11-04 华为技术有限公司 Method, devices and system for orthogonal frequency division multiplexing
CN101715240B (en) * 2009-07-23 2012-09-05 北京新岸线无线技术有限公司 Accessing method and accessing device

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2016124982A1 (en) * 2015-02-06 2016-08-11 Nokia Technologies Oy Methods and apparatus for coordination of wireless network communication
CN107210885A (en) * 2015-02-06 2017-09-26 诺基亚技术有限公司 Method and apparatus for coordinating wireless communication
CN107666453A (en) * 2016-07-28 2018-02-06 上海诺基亚贝尔股份有限公司 Transmitter and corresponding method
US20190173713A1 (en) * 2016-07-28 2019-06-06 Alcatel Lucent Transmitter and corresponding method
US10911287B2 (en) 2016-07-28 2021-02-02 Alcatel Lucent Transmitter and corresponding method
WO2024078103A1 (en) * 2022-10-09 2024-04-18 华为技术有限公司 Burst optical signal transmission method and related device

Also Published As

Publication number Publication date
CN103444146A (en) 2013-12-11
CN102594763A (en) 2012-07-18
CN103444146B (en) 2017-03-29
WO2012130090A1 (en) 2012-10-04

Similar Documents

Publication Publication Date Title
CN102790742A (en) OFDM-based data transmission method and system
CA2981355C (en) System and method of waveform design for operation bandwidth extension
CN106576346B (en) System and method for packet information indication in a communication system
CN103227765A (en) Data transmission method based on orthogonal frequency division multiplexing (OFDM) and transmitting station
US10237110B2 (en) Synchronization method and apparatus in mobile communication system
CN109156006A (en) The system and method for bandwidth usage
AU2015360989A1 (en) Training field tone plans for mixed-rate wireless communication networks
TW201008162A (en) Method of data transmission over guard sub-carriers and multi-carrier wireless device
EP2856687A1 (en) Frequency domain duplication in a long-range wireless local area network
KR20100102712A (en) Ofdma frame structures for uplinks in mimo networks
CN102868511A (en) Communication method and radio transmitter
US10158516B2 (en) Method and apparatus for transmitting data block
CN101572683A (en) Method, devices and system for orthogonal frequency division multiplexing
CN109565414B (en) Apparatus and user equipment for processing channel state information reference signal
WO2010003370A1 (en) Methods for transceiving data in multi-band orthogonal frequency division multiple access communications system and communications apparatuses utilizing the same
EP3488550A1 (en) Method and system for multi-protocol transmissions
CN105553631B (en) A kind of data transmission method, transmitting website and receiving station based on OFDM
CN102790736B (en) Methods for transmitting and receiving data and devices for transmitting and receiving data based on orthogonal frequency division multiplexing technology
CN103477598B (en) A kind of data transmission method based on OFDM and transmitting website
CN105471567B (en) A kind of data transmission method, transmitting website and receiving station based on OFDM
CN106413006B (en) A kind of ofdm communication method and system of uniform subband superposition
KR101521202B1 (en) Usage of discrete frequency spectrum in orthogonal frequency division multiplexing system, and receiving method and apparatus using discrete frequency spectrum
CN113286355B (en) Power distribution method based on OTFS-NOMA (optical transport plane-non-uniform multiple access) cross-domain transmission system
WO2010124414A1 (en) Transmitter with multiple antennas and data transmission method in the transmitter with multiple antennas
WO2013177895A1 (en) Virtual subcarrier dynamically setting method, receiving method, device and system

Legal Events

Date Code Title Description
C06 Publication
PB01 Publication
ASS Succession or assignment of patent right

Owner name: BEIJING NUFRONT MOBILE MULTIMEDIA TECHNOLOGY CO.,

Free format text: FORMER OWNER: BEIJING NUFRONT WIRELESS TECHNOLOGY CO., LTD.

Effective date: 20130403

C41 Transfer of patent application or patent right or utility model
TA01 Transfer of patent application right

Effective date of registration: 20130403

Address after: 100084 Beijing, Zhongguancun, East Road, No. 1, Tsinghua Science and Technology Park, building science and Technology Park, building No. 8, block A, floor 16

Applicant after: Beijing Nufront Mobile Multimedia Technology Co., Ltd.

Address before: 100084 Beijing, Zhongguancun, East Road, No. 1, Tsinghua Science and Technology Park, building science and Technology Park, building No. 8, block A, floor 16

Applicant before: Beijing Nufront Wireless Technology Co., Ltd.

C02 Deemed withdrawal of patent application after publication (patent law 2001)
WD01 Invention patent application deemed withdrawn after publication

Application publication date: 20121121