CN106452547A - Differential wave beam forming method used for multi-antenna relay communication system - Google Patents
Differential wave beam forming method used for multi-antenna relay communication system Download PDFInfo
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- CN106452547A CN106452547A CN201610919710.3A CN201610919710A CN106452547A CN 106452547 A CN106452547 A CN 106452547A CN 201610919710 A CN201610919710 A CN 201610919710A CN 106452547 A CN106452547 A CN 106452547A
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- terminal
- modulation
- relaying
- time slot
- information symbol
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Classifications
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04B—TRANSMISSION
- H04B7/00—Radio transmission systems, i.e. using radiation field
- H04B7/02—Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas
- H04B7/04—Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas using two or more spaced independent antennas
- H04B7/06—Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas using two or more spaced independent antennas at the transmitting station
- H04B7/0613—Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas using two or more spaced independent antennas at the transmitting station using simultaneous transmission
- H04B7/0615—Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas using two or more spaced independent antennas at the transmitting station using simultaneous transmission of weighted versions of same signal
- H04B7/0617—Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas using two or more spaced independent antennas at the transmitting station using simultaneous transmission of weighted versions of same signal for beam forming
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
- H04L27/00—Modulated-carrier systems
- H04L27/18—Phase-modulated carrier systems, i.e. using phase-shift keying
- H04L27/22—Demodulator circuits; Receiver circuits
- H04L27/233—Demodulator circuits; Receiver circuits using non-coherent demodulation
Abstract
The invention relates to a differential wave beam forming method used for a multi-antenna relay communication system. The multi-antenna relay communication system comprises a terminal A, a terminal B and a relay R with several antennas. The method is performed in a three-time-slot mode. The two terminals A and B send signals to the relay R at different time slots. The relay R carries out wave beam forming processing on the received sending signals and then broadcasts to the terminals A and B. The terminals A and B can directly carry out channel estimation according to the received broadcast signals, and interference elimination or differential decoding is not needed. Realization complexity of the communication system is reduced. The method is suitable for a condition in which several antennas are deployed in a relay terminal and an error rate of signal transmission can be reduced.
Description
Technical field
The present invention relates to wireless communication technology field, especially relates to a kind of difference for multiple antennas relay communications system
Beam-forming method.
Background technology
In wireless communication system, wireless both-way trunk technology has obtained industry in recent years due to its higher efficiency of transmission
Boundary widely pays close attention to, for wireless both-way trunk communication system, if adopting coherent communication, two mobile terminals being in communication with each other
And link terminal is required for carrying out channel estimation to obtain channel information, with the point-to-point direction communication conventional without relaying
System is compared, can be extremely complex using the channel estimation in the wireless both-way trunk communication system of coherent communication, and this will increase
Plus the complexity of two mobile terminals, in order to avoid channel estimation, noncoherent difference bi-directional relaying transmission technology can be adopted.
In the prior art, noncoherent difference bi-directional relaying transmission technology includes the non-coherent Differential relay transmission for forwarding based on decoding
Method and the non-coherent Differential relay transmission method based on amplification forwarding, the non-coherent Differential relaying biography for being forwarded based on decoding
In transmission method, the mobile terminal of two intercommunication need not carry out channel estimation, but link terminal is still needed by letter
Road is estimated to obtain channel information, to carry out signal detection and forwarding, the non-coherent Differential based on amplification forwarding is relayed
In transmission method, the mobile terminal of two intercommunication and link terminal need not all carry out channel estimation, and above two is non-
Relevant differentially bi phase relay transmission technology is all the bi-directional relaying transmission technology for employing two time slots, but, this two
The bi-directional relaying transmission technology method of time slot has the disadvantage that：1st, i.e. in first time slot, two terminals are needed to realize
Strict time synchronization can be smoothed out the detection of signal and forwarding to guarantee link terminal, but in actual communication system be
Strict time synchronization difficult to realize, so as to increased the complexity of system realization；2nd, both approaches all only have for relaying
The wireless both-way trunk communication system of single antenna, the bit error rate of transmission signal can be very high.
Content of the invention
The technical problem to be solved is to provide a kind of implementation complexity that can reduce communication system, reduce letter
The Difference Beam manufacturing process for multiple antennas relay communications system of number transmission error rates.
The technical solution adopted in the present invention is, a kind of Difference Beam shaping side for multiple antennas relay communications system
Method, multiple antennas relay communications system includes terminal A, terminal B and multiple antennas relaying R, and the antenna number that relaying R includes is M, the side
Method is divided into three time slots to be carried out, and comprises the following steps：
First time slot, the information symbol for needing to send is modulated by way of differential modulation by terminal A, then will
Information symbol after modulation is broadcast to terminal B and relaying R, and all antennas for relaying R receive the information symbol after modulation, before modulation
It is s that terminal A needs the information symbol for sendingA(n), n=1,2 ..., N, wherein N is the number of the information symbol for sending, It is the phase place of the PSK modulation system that terminal A is adopted, LAIt is PSK modulation star
The size of seat, i.e. the number of phases of PSK modulation, terminal A is poor to needing the differential modulation mode that the information symbol for sending is carried out
Divide multi-system phase-modulation, the information symbol for obtaining after modulation is xAN (), the mode of specific difference multi-system phase-modulation is：
xA(n)=xA(n-1)sA(n), n=1,2 ..., N, terminal A is by the information symbol x for obtaining after modulationA(n), n=1,2 ...,
N, is sent to relaying R, and the signal that the m root antenna of relaying R is received is： Wherein M represents the antenna number of relaying R,Represent the channel coefficients from terminal A to the m root antenna of relaying R,Represent the white Gaussian noise of the m root antenna of relaying R；
Second time slot, terminal B, will modulation to needing the information symbol for sending to be modulated by way of differential modulation
Information symbol afterwards is broadcast to terminal A and relaying R, and all antennas for relaying R receive the signal after modulation, and before modulation, terminal B is needed
The information symbol of transmission is sB(n), n=1,2 ..., N, wherein It is terminal
The phase place of the PSK modulation system that B is adopted, LBThe size of PSK modulation constellation, i.e. the number of phases of PSK modulation, terminal B is to sending out
The information symbol s for sendingBN differential modulation mode that () is carried out is difference multi-system phase-modulation, the information symbol for obtaining after modulation
For xBN (), specific difference multi-system phase modulation method is：xB(n)=xB(n-1)sB(n), n=1,2 ..., N, terminal B
By the information symbol x for obtaining after modulationB(n), n=1,2 ..., N, relaying R is sent to, the m root antenna for relaying R is received
Signal is：WhereinRepresent from terminal B to the of relaying R
The channel coefficients of m root antenna,Represent the white Gaussian noise of the m root antenna of relaying R；
3rd time slot, relays R and utilizes the signal that the first two time slot is received after multi-antenna beam shaping process, broadcast
To terminal A and terminal B, terminal A and terminal B receive broadcast singal, and the mode that the multi-antenna beam shaping is processed is that relaying R will
After the signal that the first two time slot is received carries out linear superposition, then carry out after being multiplied by phase correction factor and power amplification coefficient power amplification ratio sending out
Send, the signal that relaying R is obtained after beam shaping process is： Wherein coefficient G is used for controlling relaying transmit power,WithRepresent respectivelyWithPhase value, the value of coefficient G is：
At the end of the 3rd time slot, terminal A and terminal B estimate the transmission of other side according to respective reception signal respectively
Signal, the broadcast singal that terminal A is received in the 3rd time slot is：Wherein
zAN () represents white Gaussian noise, then terminal A can be directly according to reception signal yAN tune that the range value of () and terminal B are adopted
Planisphere processed is as follows come the sending signal for estimating terminal B：Eventually
The end broadcast singal that receives in the 3rd time slot of B is：Wherein zBN () represents
White Gaussian noise, then terminal B can be directly according to reception signal yBN modulation constellation that the range value of () and terminal A are adopted
Sending signal to estimate terminal A is as follows：
Compared with prior art, the advantage for possessing is the present invention：In the present invention, two terminals A and B can be when different
Gap sending signal, it is not necessary to strict time synchronized, so as to reduce the complexity of communication system realization；In the present invention, terminal A
Directly Signal estimation can be carried out according to reception signal with terminal B, it is not necessary to interference or differential decoding is eliminated, with prior art phase
Than with relatively low complexity；The present invention disposes the situation of many antennas suitable for link terminal, can reduce signal transmission
The bit error rate.
Description of the drawings
Fig. 1 is a kind of schematic diagram of the Difference Beam manufacturing process for multiple antennas relay communications system of the present invention；
Fig. 2 is the bit error rate performance comparison schematic diagram of Difference Beam manufacturing process proposed by the invention and additive method.
Specific embodiment
Invention is further described referring to the drawings and with reference to specific embodiment, to make those skilled in the art's reference
Specification word can be implemented according to this, and the scope of the present invention is not limited to the specific embodiment.
The present invention relates to a kind of Difference Beam manufacturing process for multiple antennas relay communications system, multiple antennas trunking traffic
System includes the relaying R of terminal A, terminal B and multiple antennas, and the antenna number that relaying R includes is M, when methods described is divided into three
Gap is carried out, and is comprised the following steps：
First time slot, the information symbol for needing to send is modulated by way of differential modulation by terminal A, then will
Information symbol after modulation is broadcast to terminal B and relaying R, and all antennas for relaying R receive the information symbol after modulation, modulation
It is s that front terminal A needs the information symbol for sendingA(n), n=1,2 ..., N, wherein N is the number of the information symbol for sending, It is the phase place of the PSK modulation system that terminal A is adopted, LAIt is PSK modulation star
The size of seat, i.e. the number of phases of PSK modulation, terminal A is poor to needing the differential modulation mode that the information symbol for sending is carried out
Divide multi-system phase-modulation, the information symbol for obtaining after modulation is xA(n), the mode of specific difference multi-system phase-modulation
For：xA(n)=xA(n-1)sA(n), n=1,2 ..., N, terminal A is by the information symbol x for obtaining after modulationA(n), n=1,
2 ..., N, relaying R is sent to, the signal that the m root antenna of the relaying R is received is： WhereinRepresent the m root antenna from terminal A to relaying R
Channel coefficients,Represent the white Gaussian noise of the m root antenna of relaying R；
Second time slot, terminal B, will modulation to needing the information symbol for sending to be modulated by way of differential modulation
Information symbol afterwards is broadcast to terminal A and relaying R, and all antennas for relaying R receive the signal after modulation, terminal B before modulation
The information symbol that need to send is sB(n), n=1,2 ..., N, wherein It is eventually
The phase place of the PSK modulation system of end B employing, LBThe size of PSK modulation constellation, i.e. the number of phases of PSK modulation, terminal B pair
The information symbol s of transmissionBN differential modulation mode that () is carried out is difference multi-system phase-modulation, the information symbol for obtaining after modulation
Number be xBN (), specific difference multi-system phase modulation method is：xB(n)=xB(n-1)sB(n), n=1,2 ..., N, terminal
B is by the information symbol x for obtaining after modulationB(n), n=1,2 ..., N, relaying R is sent to, the m root antenna for relaying R is received
Signal be：WhereinRepresent from terminal B to relaying R's
The channel coefficients of m root antenna,Represent the white Gaussian noise of the m root antenna of relaying R；
3rd time slot, relays R and utilizes the signal that the first two time slot is received after multi-antenna beam shaping process, broadcast
To terminal A and terminal B, terminal A and terminal B receive broadcast singal, and the mode that the multi-antenna beam shaping is processed is that relaying R will
After the signal that the first two time slot is received carries out linear superposition, then carry out after being multiplied by phase correction factor and power amplification coefficient power amplification ratio sending out
Send, the signal that relaying R is obtained after beam shaping process is： Wherein coefficient G is used for controlling relaying transmit power,WithRepresent respectivelyWithPhase value, the value of coefficient G is：
At the end of the 3rd time slot, terminal A and terminal B estimate the transmission of other side according to respective reception signal respectively
Signal, the broadcast singal that terminal A is received in the 3rd time slot is：Wherein
zAN () represents white Gaussian noise, then terminal A can be directly according to reception signal yAN tune that the range value of () and terminal B are adopted
Planisphere processed is as follows come the sending signal for estimating terminal B：Eventually
The end broadcast singal that receives in the 3rd time slot of B is：Wherein zBN () represents
White Gaussian noise, then terminal B can be directly according to reception signal yBN modulation constellation that the range value of () and terminal A are adopted
Sending signal to estimate terminal A is as follows：
Claims (8)
1. a kind of Difference Beam manufacturing process for multiple antennas relay communications system, it is characterised in that：Multiple antennas trunking traffic
System includes terminal A, terminal B and multiple antennas relaying R, and the antenna number that relaying R includes is M, and methods described is divided into three time slots
Carry out, comprise the following steps：
(1), first time slot, the information symbol for needing to send is modulated by way of differential modulation by terminal A, then will
Information symbol after modulation is broadcast to terminal B and relaying R, and all antennas for relaying R receive the signal after modulation；
(2), second time slot, the information symbol for needing to send is modulated by way of differential modulation by terminal B, then will
Information symbol after modulation is broadcast to terminal A and relaying R, and all antennas for relaying R receive the signal after modulation；
(3), the 3rd time slot, relays modulated signal that the first two time slot receives by R place by way of beam shaping is processed
After reason, terminal A and terminal B is broadcast to, terminal A and terminal B are respectively received broadcast singal, the mode that the beam shaping is processed
It is that relaying R carries out the modulated signal that the first two time slot is received after linear superposition, then is multiplied by phase correction factor and power is put
It is transmitted after big coefficient；
(4), at the end of the 3rd time slot, terminal A and B estimate sending out for other side respectively according to the broadcast singal being respectively received
The number of delivering letters.
2. a kind of Difference Beam manufacturing process for multiple antennas relay communications system according to claim 1, its feature
It is：In the first time slot, it is s that terminal A needs the information symbol for sendingA(n), n=1,2 ..., N, wherein N is the information for sending
The number of symbol, It is the phase place of the PSK modulation system that terminal A is adopted, LA
The size of PSK modulation constellation, i.e. the number of phases of PSK modulation.
3. a kind of Difference Beam for multiple antennas relay communications system according to claim 1 or claim 2 shapes
Method, it is characterised in that：In the first time slot, information symbol s of terminal A to transmissionAN differential modulation mode that () is carried out is difference
Multi-system phase-modulation, the information symbol after modulation is xAN (), difference multi-system phase modulation method is：xA(n)=xA(n-1)
sA(n), n=1,2 ..., N, terminal A is by the information symbol x for obtaining after modulationA(n), n=1,2 ..., N, relaying R is sent to,
The modulated signal that receives of m root antenna of relaying R is：N=1,2 ..., N, m=1,
2 ..., M, whereinRepresent the channel coefficients from terminal A to the m root antenna of relaying R,Represent the m root day of relaying R
The white Gaussian noise of line.
4. a kind of Difference Beam manufacturing process for multiple antennas relay communications system according to claim 1, its feature
It is：First time slot, it is s that terminal B needs the information symbol for sendingB(n), n=1,2 ..., N, wherein It is the phase place of the PSK modulation system that terminal B is adopted, LBIt is PSK modulation star
The size of seat, i.e. the number of phases of PSK modulation.
5. a kind of Difference Beam for multiple antennas relay communications system according to claim 1 or claim 4 shapes
Method, it is characterised in that：Information symbol s of terminal B to transmissionBN differential modulation mode that () is carried out is difference multi-system phase place
Modulation, the information symbol after modulation is xBN (), difference multi-system phase modulation method is：xB(n)=xB(n-1)sB(n), n=
1,2 ..., N, terminal B is by the information symbol x for obtaining after modulationB(n), n=1,2 ..., N, relaying R is sent to, relays the of R
The modulated signal that m root antenna is received is：N=1,2 ..., N, m=1,2 ..., M, whereinRepresent the channel coefficients from terminal B to the m root antenna of relaying R,Represent the Gauss white noise of the m root antenna of relaying R
Sound.
6. a kind of Difference Beam manufacturing process for multiple antennas relay communications system according to claim 1, its feature
It is：In 3rd time slot, the signal that relaying R is obtained after the mode that beam shaping is processed is processed is：N=1,2 ..., N, m=1,2 ..., M, wherein coefficient G is used for controlling
System relaying transmit power,WithRepresent respectivelyWithPhase value, the value of coefficient G is：
7. a kind of Difference Beam manufacturing process for multiple antennas relay communications system according to claim 1, its feature
It is：The broadcast singal that terminal A is received in the 3rd time slot is：N=1,2 ..., N, its
Middle zAN () represents white Gaussian noise, terminal A can be directly according to reception signal yAN tune that the range value of () and terminal B are adopted
Planisphere processed estimating the sending signal of terminal B is：N=1,2 ..., N.
8. a kind of Difference Beam manufacturing process for multiple antennas relay communications system according to claim 1, its feature
It is：The broadcast singal that terminal B is received in the 3rd time slot is：N=1,2 ..., N, its
Middle zBN () represents white Gaussian noise, terminal B can be directly according to reception signal yBN tune that the range value of () and terminal A are adopted
Planisphere processed estimating the sending signal of terminal A is：N=1,2 ..., N.
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106685509A (en) * | 2017-03-17 | 2017-05-17 | 谭毅 | 5G millimeter wave communication method and corresponding beam forming method |
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| US20160191134A1 (en) * | 2014-12-30 | 2016-06-30 | Electronics And Telecommunications Research Institute | Beam formation for data transmission for two-way multi-antenna relay system with physical network coding |
| CN106027135A (en) * | 2016-04-27 | 2016-10-12 | 浙江万里学院 | Difference multiplication bidirectional relay transmission method based on channel quality |
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| CN101529741A (en) * | 2006-10-26 | 2009-09-09 | 高通股份有限公司 | Repeater techniques for multiple input multiple output utilizing beam formers |
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