CN103078820B - A kind of efficiently and directionally wireless communications method - Google Patents

A kind of efficiently and directionally wireless communications method Download PDF

Info

Publication number
CN103078820B
CN103078820B CN201210477347.6A CN201210477347A CN103078820B CN 103078820 B CN103078820 B CN 103078820B CN 201210477347 A CN201210477347 A CN 201210477347A CN 103078820 B CN103078820 B CN 103078820B
Authority
CN
China
Prior art keywords
signal
amp
antenna
transmitting antenna
receiving apparatus
Prior art date
Application number
CN201210477347.6A
Other languages
Chinese (zh)
Other versions
CN103078820A (en
Inventor
宋向辉
王笑京
李南
刘楠
杜磊
Original Assignee
交通运输部公路科学研究所
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 交通运输部公路科学研究所 filed Critical 交通运输部公路科学研究所
Priority to CN201210477347.6A priority Critical patent/CN103078820B/en
Publication of CN103078820A publication Critical patent/CN103078820A/en
Application granted granted Critical
Publication of CN103078820B publication Critical patent/CN103078820B/en

Links

Abstract

The present invention discloses a kind of efficiently and directionally wireless communications method, the phase place of signal is launched by control, make the signal specific location in space that two antenna unit send, correctly superposition can synthesize original signal, and the synthesis in other orientation causes signal distortion, original signal can not be recovered, and then define the wireless communication link of a kind of orientation. The present invention under the prerequisite of directional characteristic demand considering radio communication system, can solve based on the radio communication system high peak-to-average power ratio of OFDM standard and the technical problem of power amplifier linearization.

Description

A kind of efficiently and directionally wireless communications method

Technical field

The invention belongs to wireless communication technology field, relate generally to a kind of new wave beam shaping transmitter architecture and directional radio communication implementation step.

Prior art

(1) OFDM standard radio ultra wide band system peak-to-average force ratio Question background summary

The Technology of Ultra can be divided into two kinds of standards according to its technology feature, a kind of is the Technology of Ultra based on pulse standard, for various reasons, only it is applied to some special industry field at present, such as the ultra-wide band radio-frequency identification tag technology in logistic industry; Another kind is the Technology of Ultra based on OFDM (OrthogonalFrequencyDivisionMultiplexing) standard, the application of this standard is comparatively extensive, as all defined OFDM physical layer in IEEE802.11a/b/e/g, LTE-Advanced also applies the Technology of Ultra based on OFDM standard. Because of its being widely used in mobile communication and other multiple industry fields, the Technology of Ultra based on OFDM standard had become main technological evolvement basis already, was also the primary study object of various technical study project.

The existing super broad band radio communication system based on OFDM standard mainly contains two big technical barriers, and one is frequency offset issues; Another is then peak-to-average force ratio (Peak-to-AveragePowerRatio, PAR) problem.

Frequency shift mainly causes because of receipts/emitter high-speed mobile, and the impact caused is inter-carrier interference (Inter-Carrierinterference, ICI), and inter-carrier interference can make ofdm system subcarrier lose orthogonality, thus reduces communication quality. At present, mainly frequency shift impact is improved with statistical method.

Peak-to-average force ratio problem mainly because of modulation signal in OFDM standard the Technology of Ultra be by the modulation signal of multiple subcarrier add with and become, therefore, the signal envelope that emitter is launched is not only inconstant, and in a relatively large scope fluctuate. For ensureing the high peak-to-average power ratio signal quality sent, system must have wider linearity range. But, the lifting of the linear lag makes the degradation in efficiency of power amplifier (PowerAmplifier, PA). Common ofdm system adopts A class (ClassA) power amplifier that efficiency is lower to realize the requirement of the linear lag. At present, solve the feasible technology of the contradiction between high order modulation (high peak-to-average power ratio) signalling system (ofdm system) neutral line degree and efficiency and new transmitter architecture can be adopted to realize, mainly contain following several:

A () adopts predistortion and the form of Doherty power amplifier combination;

(b) envelop following technology (EnvelopeTracking, ET);

C () envelope is deleted and recovery technology (EnvelopeEliminationandRestoration, EER), also known as polar coordinate transmitter structure (PolarTransmitter);

D () uses the linear transmitter (LinearizationImplementedwithNonlinearComponent of non-linear device, LINC), this kind of structure is also called sign reversing amplifier structure (OutphasingAmplifiication). The amplitude information of modulation signal is converted to Phasic information by mathematic(al) manipulation by Outphasing structure, characteristic according to trigonometrical function generates the constant envelope signal of two-way antithesis, constant amplitude, two paths of signals peak-to-average force ratio is low respectively by non-linear high efficiency power amplifier, then is original signal by power combing. This kind of method effectively improves the efficiency of emitter when ensureing linear transmitter degree, but due to final signal synthesis will on sheet or the power synthesis network of plate level (such as Wilkinson synthesizer) complete, therefore can introduce certain output rating loss and signal distortion.

(2) directional radio communication Question background summary

Directional radio communication technology can improve communication security effectively, and directional characteristic can be utilized to realize more special applications.

The wireless communication technology with directional characteristic is mainly reflected in spatial division multiplexing (SpaceDivisionMultiplexing at present, SDM) on technology and beam forming technique (Beamforming), generally adopt intelligent antenna technology, the general antenna array adopting certain geometric format, the gain of antenna of specific direction strengthened by numeral base band algorithm or weakens during transmission, thus only with the target transmission information in specified range. The antenna array receiver transmitter signal of certain geometric format generally also can be adopted during reception, and adopt statistical analysis algorithms to carry out the angle of arrival (DirectionOfArrival, DOA) estimate, thus the signal of specific objective is separated from the signal in ground unrest and other directions, this process is also referred to as beam forming technique. At present, compare ripe algorithm and have sub space decomposition etc.

Summary of the invention

It is an object of the invention to provide a kind of efficiently and directionally wireless communications method, under the prerequisite of directional characteristic demand considering radio communication system, solve the technical problem of the radio communication system high peak-to-average power ratio based on OFDM standard.

In order to realize foregoing invention object, the present invention adopts following technical scheme.

A kind of efficiently and directionally wireless communications method, the phase place of signal is launched by control, make the signal specific location in space that two in two antenna transmit machine transmitting antenna sends, correctly superposition can synthesize original signal, and the synthesis in other orientation causes signal distortion, original signal can not be replied out, and then define the wireless communication link of a kind of orientation; Implementation step is as follows:

(1) it is phase angle information by the amplitude convert information in high order modulation signal;

(2) receiving apparatus relative transmitter position angle is estimated;

(3) phase compensation value is calculated;

(4) emitter sends information;

(5) emitter receiving feedback information, if feedback and sending terminates, enters step (6), if feedback but send not yet terminates or not feedback, then returns step (2);

(6) terminate.

Described high order modulation signal is the decomposition of permanent envelope and the phase compensation function that complete the signal that peak-to-average force ratio is high by baseband signal processing module, adopt quadrature up-conversion structure Direct conversion to transmission carrier frequency by up-converter module again, make the signal power of the efficient non-linear power amplifier of feed-in keep certain level through driving amplifier, launch by antenna.

Two transmitting antennas in described two antenna transmit machine, have following geometric relationship with the layout of single antenna receiving apparatus,

d 1 ≈ l 1 - d 0 c o s θ 2 d 2 ≈ l 1 + d 0 c o s θ 2

d0For transmitting antenna spacing, unit rice (m); d2It is first transmitting antenna and receiving antenna spacing, unit rice (m); d1It is the 2nd transmitting antenna and receiving antenna spacing, unit rice (m); �� is receiving apparatus relative transmitter position angle, namely through two transmitting antenna line mid points and the straight line of receiver antenna and the angle of two transmitting antenna lines; l1For receiving antenna is to the distance of receiving apparatus relative transmitter position angle Strahlungseintritt, unit rice (m).

The step of described calculating phase compensation value is as follows:

ψ ( τ ) = arccos a ( τ ) A max ‾ - ω c d 0 2 v c c o s θ

A (��) is the range value produced after modulation, it is possible to the modulation system according to adopting calculates; AmaxIt is maximum amplitude value corresponding in the constellation symbol to be launched, it is possible to the modulation system according to adopting calculates; vcFor the light velocity, unit rice/second (m/s); ��cFor carrier angular frequencies, unit radian/second (rad/s); d0For transmitting antenna spacing, unit rice (m); �� is receiving apparatus relative transmitter position angle, the straight line being namely connected with receiver antenna through two transmitting antenna line mid points and the angle of two transmitting antenna lines, unit degree (��); �� (��) is phase compensation value.

The effect of the present invention is as follows: if transmitting antenna is omnidirectional antenna, it is possible to allows and is in the correct demodulation of receiving apparatus near any �� angle, is in outside this angle scope owing to the increase of error vector amplitude (EVM) value then cannot correctly demodulation. Impracticable of the present invention is upper or the power combing of plate level, therefore, avoids on sheet and loss that plate level power combing causes and signal distortion problem.

Accompanying drawing explanation

Fig. 1 is the transmitter architecture schematic diagram of the present invention.

Fig. 2 is two antenna unit and the single antenna receiving apparatus layout geometric relationship figure of the present invention.

Fig. 3 (a)-(m) is the deviation of receiving apparatus along with angle of different angles range position of the present invention, the calculation result figure that EVM value also increases thereupon.

Embodiment

The transmitter architecture of the present invention as shown in Figure 1, mainly comprises baseband signal processing module, orthometric up-conversion module, driving amplifier, efficient non-linear power amplifier, transmitting antenna and receiving antenna array composition. Wherein, baseband signal processing module completes the decomposition of permanent envelope and the phase compensation function of the signal that peak-to-average force ratio is high. Up-converter module adopts quadrature up-conversion structure Direct conversion to transmission carrier frequency. Driving amplifier makes the signal power of feed-in power amplifier keep certain level, and then ensures high efficiency realization.

Implementation step is as follows:

(1) it is phase angle information by the amplitude convert information in high order modulation signal;

(2) the azimuthal position angle of receiving apparatus relative transmitter is estimated;

(3) phase compensation value is calculated;

(4) launch end and send information;

(5) launch end receiving feedback information, if feedback and sending terminates, enter step (6), if feedback but send not yet terminates or not feedback, then return step (2);

(6) terminate.

Such as Fig. 2, for two antenna unit, shown emitter (double antenna) and receiving apparatus (single antenna) layout have following geometric relationship,

d 1 ≈ l 1 - d 0 c o s θ 2 d 2 ≈ l 1 + d 0 c o s θ 2 - - - ( 1 )

Adopt existing algorithm, such as MUSIC algorithm etc., to receive antenna array receiver to signal carry out diversity, estimate the position angle of intended recipient end relative transmission end, be referred to as angle-of-arrival estimation module.

It is modulated to example with 16QAM, if waveform expression formula corresponding to the constellation symbol to be sent of t emitter is as shown in (2) formula,

xQAM(t)=a (t) cos [��ct+��(t)],t��[0,TSymbol](2)

If corresponding, amplitude information a (t) is done following conversion,

ψ ( t ) = arccos [ a ( t ) A max ] - - - ( 3 )

(3) in formula, AmaxIt is maximum amplitude value corresponding in the constellation symbol to be launched, it is possible to the modulation system according to adopting calculates. On this basis, the modification of signal launched by each antenna of emitter is following form,

x TX 1 ( t ) = A m a x 2 c o s [ ω c t + φ ( t ) + ψ ( t ) ] x T X 2 ( t ) = A m a x 2 c o s [ ω c t + φ ( t ) - ψ ( t ) ] - - - ( 4 )

Accepting the superposition that the signal that machine place receives is two signals,

x R X ( t ) = x TX 1 ( t - d 1 v c ) + x TX 2 ( t - d 2 v c ) = A max 2 cos [ ω c ( t - l 1 v c + d 0 cos θ 2 v c ) + φ ( t - l 1 v c + d 0 cos θ 2 v c ) + ψ ( t - l 1 v c + d 0 cos θ 2 v c ) ] + A max 2 cos [ ω c ( t - l 1 v c - d 0 cos θ 2 v c ) + φ ( t - l 1 v c - d 0 cos θ 2 v c ) + ψ ( t - l 1 v c - d 0 cos θ 2 v c ) ] - - - ( 5 )

(5) v in formulacFor the light velocity, again because of d0cos��<<vc, soMake again(5) formula can simplify following form further,

x R X ( t ) = x TX 1 ( t - d 1 v c ) + x TX 2 ( t - d 2 v c ) = A max 2 cos &lsqb; &omega; c ( t + d 0 cos &theta; 2 v c ) + &phi; ( &tau; ) + &psi; ( &tau; ) &rsqb; + A max 2 cos &lsqb; &omega; c ( &tau; - d 0 cos &theta; 2 v c ) + &phi; ( &tau; ) - &psi; ( &tau; ) &rsqb; = A max cos &lsqb; &omega; c &tau; + &phi; ( &tau; ) &rsqb; cos &lsqb; &psi; ( &tau; ) + &omega; c d 0 cos &theta; 2 v c &rsqb; - - - ( 6 )

Consider decay factor, if �� is decay factor, then finally can obtain

x R X ( t ) = &alpha;A max cos &lsqb; &omega; c &tau; + &phi; ( &tau; ) &rsqb; cos &lsqb; &psi; ( &tau; ) + &omega; c d 0 2 v c cos &theta; &rsqb; - - - ( 7 )

If &theta; = &pi; 2 , Then have

xRX(t)=�� a (t) cos [��c��+��(��)](8)

Visible being recovered by space overlapping at former modulation symbol waveform, correspondingly, within the scope of certain angle, signal can be received the correct demodulation of machine, and after exceeding certain angle scope, signal can not by correct demodulation.

Utilize this principle, can set equally the receiving apparatus within the scope of a certain angle can correctly demodulation, namely should have at �� angle place

a ( &tau; ) = A m a x c o s &lsqb; &psi; ( &tau; ) + &omega; c d 0 2 v c c o s &theta; &rsqb; - - - ( 9 )

Launch (9) formula and finally can obtain (10) formula

&psi; ( &tau; ) = arccos ( a ( &tau; ) A m a x ) - &omega; c d 0 2 v c c o s &theta; - - - ( 10 )

If transmitting antenna is omnidirectional antenna, just can allow according to (10) formula and be in the correct demodulation of receiving apparatus near any �� angle, be in outside this angle scope owing to the increase of error vector amplitude (EVM) value then cannot correctly demodulation.

Calculating parameter setting is as shown in table 1, (7) formula of utilization and (10) formula, taking 15 �� as interval to [0 ��, 180 ��] reception in scope calculates, namely suppose that receiving apparatus is in certain with within the scope of special angle, gained result is as shown in Figure 3, therefrom can find out the desirable 16-QAM constellation figure variation range that the receiving apparatus in different angles range position receives, along with the deviation of receiving apparatus angle, EVM value also increases thereupon, and constellation point can not be received the correct demodulation of machine gradually. The scope of correct receiving demodulation is subject to the restriction of system physical parameter characteristic, just can set correct demodulation scope width as changed transmitting antenna spacing, frequency, thus ensure that the directional property of radio communication. Namely by launching the phase place of signal in control, make signal that two antenna unit send in space specific position go out and correctly superposition can synthesize original signal, and the synthesis in other orientation causes signal distortion, can not reply out former is signal, defines the wireless communication link of a kind of orientation. This kind of structure, impracticable upper or the power combing of plate level, therefore, avoids on sheet and loss that plate level power combing causes and signal distortion problem.

Table 1 simulation parameter sets

Parameter name Numerical value Carrier frequency 5.8GHz Angle scope ��5�� Antenna interval 0.015m

Claims (3)

1. an efficiently and directionally wireless communications method, the phase place of signal is launched by control, make the signal specific location in space that two in two antenna transmit machine transmitting antenna sends, correctly superposition can synthesize original signal, and the synthesis in other orientation causes signal distortion, original signal can not be recovered, and then define the wireless communication link of a kind of orientation; Implementation step is as follows:
(1) it is phase angle information by the amplitude convert information in high order modulation signal;
(2) receiving apparatus relative transmitter position angle is estimated;
(3) phase compensation value is calculated;
(4) emitter sends information;
(5) emitter receiving feedback information, if feedback and sending terminates, enters step (6), if feedback but send not yet terminates or not feedback, then returns step (2);
(6) terminate;
The step of described calculating phase compensation value is as follows:
,
A (��) is the range value produced after modulation, and the modulation system according to adopting calculates; AmaxBeing maximum amplitude value corresponding in the constellation symbol to be launched, the modulation system according to adopting calculates; vcFor the light velocity, unit rice/second (m/s); ��cFor carrier angular frequencies, unit radian/second (rad/s); d0For transmitting antenna spacing, unit rice (m); �� is receiving apparatus relative transmitter position angle, namely through two transmitting antenna line mid points and receiver antenna
Straight line and the angle of two transmitting antenna lines, unit degree (��); �� (��) is phase compensation value.
2. a kind of efficiently and directionally wireless communications method according to claim 1, described high order modulation signal is the decomposition of permanent envelope and the phase compensation function that complete the signal that peak-to-average force ratio is high by baseband signal processing module, adopt quadrature up-conversion structure Direct conversion to transmission carrier frequency by up-converter module again, make the signal power of the efficient non-linear power amplifier of feed-in keep certain level through driving amplifier, launch by antenna.
3. a kind of efficiently and directionally wireless communications method according to claim 1, two transmitting antennas in described two antenna transmit machine, have following geometric relationship with the layout of single antenna receiving apparatus,
,
d0For transmitting antenna spacing, unit rice (m); d2It is first transmitting antenna and receiving antenna spacing, unit rice (m); d1It is the 2nd transmitting antenna and receiving antenna spacing, unit rice (m); �� is receiving apparatus relative transmitter position angle, namely through two transmitting antenna line mid points and the straight line of receiver antenna and the angle of two transmitting antenna lines; l1For receiving antenna is to the distance of receiving apparatus relative transmitter position angle Strahlungseintritt, unit rice (m).
CN201210477347.6A 2012-11-21 2012-11-21 A kind of efficiently and directionally wireless communications method CN103078820B (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN201210477347.6A CN103078820B (en) 2012-11-21 2012-11-21 A kind of efficiently and directionally wireless communications method

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN201210477347.6A CN103078820B (en) 2012-11-21 2012-11-21 A kind of efficiently and directionally wireless communications method

Publications (2)

Publication Number Publication Date
CN103078820A CN103078820A (en) 2013-05-01
CN103078820B true CN103078820B (en) 2016-06-01

Family

ID=48155229

Family Applications (1)

Application Number Title Priority Date Filing Date
CN201210477347.6A CN103078820B (en) 2012-11-21 2012-11-21 A kind of efficiently and directionally wireless communications method

Country Status (1)

Country Link
CN (1) CN103078820B (en)

Families Citing this family (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN103560758B (en) * 2013-11-15 2016-09-07 上海无线电设备研究所 A kind of power amplifier for polar coordinate transmitter
US9860893B2 (en) * 2013-11-19 2018-01-02 Intel IP Corporation Frame structure with reduced signal field and method for high-efficiency Wi-Fi (HEW) communication
CN106102156A (en) * 2016-05-30 2016-11-09 成都理工大学 Linearisation transmission method based on multiple antennas

Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101951355A (en) * 2010-09-16 2011-01-19 华南理工大学 Method for reducing peak-to-average ratio of lead code of OFDM
CN102223168A (en) * 2011-06-02 2011-10-19 西安电子科技大学 Combined transmit beamforming method based on array antenna and MIMO

Family Cites Families (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP1791313B1 (en) * 2005-10-25 2008-08-20 Fujitsu Ltd. Communications systems and methods using selected mapping for OFDM signals
US20070177492A1 (en) * 2006-01-27 2007-08-02 Qualcomm Incorporated Methods and tools for expanding coverage of an ofdm broadcast transmitter via transmit timing advance

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101951355A (en) * 2010-09-16 2011-01-19 华南理工大学 Method for reducing peak-to-average ratio of lead code of OFDM
CN102223168A (en) * 2011-06-02 2011-10-19 西安电子科技大学 Combined transmit beamforming method based on array antenna and MIMO

Also Published As

Publication number Publication date
CN103078820A (en) 2013-05-01

Similar Documents

Publication Publication Date Title
JP6199434B2 (en) Single stream phase tracking during channel estimation in ultra-high throughput wireless MIMO communication systems
USRE46750E1 (en) System and method for antenna diversity using equal power joint maximal ratio combining
US8824595B2 (en) High efficiency, remotely reconfigurable remote radio head unit system and method for wireless communications
US10027354B2 (en) Phased array weighting for power efficiency improvement with high peak-to-average power ratio signals
US8351988B2 (en) Methods and systems for transmitting an information signal in a multiple antenna communication system
EP2388931B1 (en) Method and system for mixed analog/digital beamforming in wireless communication systems
CN102111200B (en) Native medium access control support for beamforming
EP3110231B1 (en) High efficiency, remotely reconfigurable remote radio head unit system and method for wireless communications
CN104579440B (en) A kind of design method of the direction modulated signal based on retrodirective array
EP1313278B1 (en) Method and apparatus for adaptive digital predistortion in a radio transmitter
CN102158269B (en) Communication system and method for channel estimation and beamforming using a multi-element array antenna
CN101517920B (en) Beamforming by antenna puncturing
CN101523736B (en) Mobile assisted downlink beamforming with antenna weight feedback
CN103210692B (en) Location
CN101675603B (en) Multiple antennas transmit diversity scheme
US9998200B2 (en) Systems and methods for a fronthaul network
US8248909B2 (en) Method and device for the baseband process of the space-time/space-frequency/spatial diversity transmitter
CN101569127B (en) Base station device
EP2748941B1 (en) Apparatus and method for selecting beam in wireless communication system
CN101515917B (en) Multi-user wireless communication system based on both-way trunk and method thereof
US20130017858A1 (en) Method and System of Beamforming a Broadband Signal Through a Multiport Network
US10075321B2 (en) Exploitation of frequency twisted waves in wireless communication systems to increase transmission capacity thereof
CN101112061B (en) Multi-carrier receiver and method for separating transmitted signal in multi-antenna system and method
CN101510799B (en) Wireless communication device and wireless communication method
US20060120469A1 (en) Multiple antenna multicarrier transmitter and method for adaptive beamforming with transmit-power normalization

Legal Events

Date Code Title Description
PB01 Publication
C06 Publication
SE01 Entry into force of request for substantive examination
C10 Entry into substantive examination
GR01 Patent grant
C14 Grant of patent or utility model
CF01 Termination of patent right due to non-payment of annual fee

Granted publication date: 20160601

Termination date: 20161121

CF01 Termination of patent right due to non-payment of annual fee