CN101977096A - Amplify-and-forward (AF) cooperative communication method for performing network coding on MPSK signal - Google Patents
Amplify-and-forward (AF) cooperative communication method for performing network coding on MPSK signal Download PDFInfo
- Publication number
- CN101977096A CN101977096A CN 201010531380 CN201010531380A CN101977096A CN 101977096 A CN101977096 A CN 101977096A CN 201010531380 CN201010531380 CN 201010531380 CN 201010531380 A CN201010531380 A CN 201010531380A CN 101977096 A CN101977096 A CN 101977096A
- Authority
- CN
- China
- Prior art keywords
- user
- signal
- time slot
- base station
- mpsk
- 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.)
- Granted
Links
Images
Landscapes
- Mobile Radio Communication Systems (AREA)
- Radio Relay Systems (AREA)
Abstract
The invention discloses an amplify-and-forward (AF) cooperative communication method for performing network coding on an MPSK signal, belonging to the technical field of wireless communication. The method is implemented as follows: based on a system model for communication between two wireless users which relay with each other and a base station, respectively modulating data for sent MPSK at a user side at time slot 1 and at time slot 2; performing AF on received signals and local signals after network coding by a relay user at time slot 3; and performing maximum likelihood detection on the received three time slots by the base station to recover user data. Simultaneously, the technical scheme of the invention also provides a method similar to the maximum likelihood detection aiming to the BPSK, which can simplify the detection operation complexity of a receiving end. The method can be suitable for occasions such as a sensor network and the like which have low requirements on relays and can save one transmission time slot under the condition of having the same error rate as a common AF cooperation communication method, thus saving frequency spectrum resources (improving the frequency spectrum resource utilization factor) and total system transmission power.
Description
Technical field
The invention belongs to wireless communication technology field, relate to network coding technique and communication for coordination technology.
Background technology
Network coding technique is at first proposed by people such as Ahlswede, and its purpose mainly is the message capacity that is used to promote cable network.People such as Yingda Chen are incorporated into network coding technique in the communication for coordination at first.They suppose that the user-user information transmission is reliable, studied decoding forward pass (DF) collaborative communication method of coding Network Based (NC) on this basis, proved network code introduced and to have improved overall system performance in the communication for coordination and (improve network transmission capacity and throughput of system, strengthen network robustness, aspects such as balance network load).In addition, there is document to propose a kind of spectral efficient DF collaborative communication method of coding Network Based, in the method, the collaborative user who serves as the relaying role decodes collaborative partner's data, and carry out XOR with its data, thereby the realization network code is saved transmission time slot, obtains the lifting of spectrum efficiency.But the shortcoming of this method maximum is its complexity height, because: trunk subscriber at first needs collaborative partner's data are deciphered and carried out XOR with its data, and the result to XOR encodes once more then; And decode procedure is taked usually is the loop iteration decode procedure, and its computation complexity and very big to spending of hardware is very high to the requirement of trunk subscriber, is difficult to realize.
In some application scenarios (as sensor network), the collaborative user can not satisfy so high complexity requirement, in such scene, amplify forward pass (AF) communication for coordination owing to realize simply simultaneously can obtaining the full diversity exponent number, become first-selected cooperative communication mode.Therefore, how network coding technique is applied in the AF communication for coordination, thereby the gain of acquisition systematic function is a good problem to study.
Through behind the network code, in the time slot of transmitting coding back information, the user is identical code word bits with the trunk subscriber transmission.The AF Synergistic method (AF-NC) of coding Network Based utilizes this characteristic to improve spectrum efficiency just.In optimum receiving algorithm, the base station will inevitably be by realizing that to this symbol high specific merges someway, and what kind of simple and effective power division mode of this employing can make the signal to noise ratio that receives combined signal the highest again, and this also becomes one of problem demanding prompt solution.
In the base station, carry out Maximum Likelihood Detection to received signal.But owing to maximum likelihood (Maximum Likelihood at the AF-NC method, ML) receiver is comparatively complicated, keeping whether can proposing a kind of method of reseptance of simplification under the prerequisite of bit error rate performance preferably, how to realize that the detection method of simplifying also is the problem that needs research.
Summary of the invention
The present invention is based on the system model that communicates between two wireless users of mutual relaying and the base station, proposed a kind of amplification forward pass collaborative communication method that mpsk signal is carried out network code.This method is based on the AF collaborative communication method (AF-NC) of simple network coding, adopt maximum likelihood detection method, make that when adopting the MPSK modulation AF-NC can obtain and the suitable performance of common AF collaborative communication method when improving the availability of frequency spectrum, saving transmitted power.
Technical scheme of the present invention is:
A kind of amplification forward pass collaborative communication method that mpsk signal is carried out network code, based on the system model (as shown in Figure 1) that communicates between two users of mutual relaying and the base station, adopt time-multiplexed transmission means, and the hypothesis channel is a Rayleigh channel, as shown in Figure 2, may further comprise the steps:
Step 1: at time slot 1, adopt the signal of coded data after the MPSK modulation of conventional transmitted power broadcasting user 1 self by user 1, differentiation is detected to the user's 1 that receives signal in user 2 and base station;
Step 2: at time slot 2, adopt the signal of coded data after the MPSK modulation of conventional transmitted power broadcasting user 2 self by user 2, differentiation is detected to the user's 2 that receives signal in user 1 and base station;
Step 3: by the good and bad result of base station by descending control signaling channel feedback two up channel signal to noise ratios;
Step 4: at time slot 3, adopt the power that surpasses conventional transmitted power to send the data of network code by the higher user of channel signal to noise ratio, Combined Treatment is carried out to 3 received signals of time slot in the base station, finally obtains user 1 and user's 2 coded data.
In the such scheme: 1) the described MPSK modulation system of step 1 and step 2 is a kind of MPSK modulation system based on the constellation point mapping mode of justifying the territory; 2) process of network code described in the step 4 is that the product calculation that adopts user 1 and user's 2 coded data to carry out analog domain replaces the XOR of digital signal in the common network code to realize; 3) Combined Treatment described in the step 4 is the base station obtains user 1 and user's 2 coded data after carrying out Maximum Likelihood Detection, demodulation to 3 received signals of time slot a detected value.
In 3 kinds of transmission modes as shown in Figure 2, guaranteed that all the diversity that the base station receives two users' data is 2 (2 diversity orders can be transmitted and obtain to verified AF-NC method in 3 time slots).AF communication for coordination transmission method is compared no collaborative transmission method, avoided the double possibility that signal is disturbed of deep fade of same channel, the high specific of the same data of two channels being sent by the base station merges (weighted sum), and then transmission signals is detected.And AF-NC scheme proposed by the invention, increased the network code part on this basis, compare with AF communication for coordination transmission method, realizing to save a transmission time slot under the suitable error rate condition, thereby saved frequency spectrum resource (having improved frequency spectrum resource utilization rate), improved the message transmission rate (in the unit interval, the transmission quantity of common AF method is 1/2 bit, and the transmission quantity of AF-NC method provided by the invention can reach 2/3 bit) of system; Under identical transmitting power total amount, the transmitting power of the 4th time slot saving can be increased in the 3rd time slot, like this, under identical channel condition, can further improve the signal to noise ratio that transmits, thereby realize the lower error rate.At data sending terminal, the present invention adopts the MPSK modulation system, and M successive bits is mapped as a symbol, and modulation result is that complex signal transmits on channel.At the base station receiving terminal 3 received signals are carried out Maximum Likelihood Detection, and then carry out demodulation, obtain the detected value of coded data at last, greatly degree has reduced computational complexity, greatly alleviates hardware and realizes difficulty (as shown in Figure 3).
To sum up, the present invention is based on the system model that communicates between two wireless users of mutual relaying and the base station, proposed a kind of amplification forward pass collaborative communication method that mpsk signal is carried out network code.This method is based on the AF collaborative communication method (AF-NC) of simple network coding, aspect the input of receiving terminal, adopt maximum likelihood detection method, make when adopting the MPSK modulation, realizing to save a transmission time slot under the suitable error rate condition, thereby saving frequency spectrum resource (having improved frequency spectrum resource utilization rate) and the total transmitted power of system.When adopting the bpsk signal modulation system, the present invention has carried out approximate processing to maximum likelihood detection method aspect the input of receiving terminal, thereby greatly degree has reduced computational complexity, greatly alleviates hardware and realizes difficulty.In addition, the present invention compares with AF communication for coordination transmission method, owing to saved a transmission time slot, under identical transmitting power total amount, the transmitting power of the 4th time slot saving can be increased in the 3rd time slot, like this, under identical channel condition, can further improve the signal to noise ratio that transmits, thereby realize the lower error rate.
Description of drawings
Fig. 1 is a system applies scene schematic diagram.User 1 and user 2 are to the base station transmits data, and for avoiding interference, two users adopt the time division multiplexing transmission.
Fig. 2 be non-collaborative, AF collaborative, the AF-NC collaborative transmission method.Fig. 2 (a) and (b) represent non-collaborative and common AF collaborative transmission method respectively.In non-collaborative transmission method, user 1 is in time slot 1 and the identical data of time slot 3 transmission; User 2 is in the identical data of time slot 2 time slots, 4 transmission.In common AF transmission method, user 1 is in time slot 1 transmission data, and user 2 and base station receive; User 2 is in time slot 4 re-transmission users' 1 data, and user 1 and base station receive.Fig. 2 (c) represents AF-NC collaborative transmission method provided by the invention.
Fig. 3 is the approximate Maximum Likelihood Detection schematic diagram of AF-NC.
Fig. 4 is AF-NC error rate theory analysis and simulation result (the up average signal-to-noise ratio of two users equates).
Fig. 5 is AF-NC error rate theory analysis and simulation result (user's 2 up average noises are 20dB).
Fig. 6 is an AF-NC MPSK modulation error rate simulation result (the up average signal-to-noise ratio of two users equates).
Embodiment
Below in conjunction with accompanying drawing, the present invention is further specified.
A kind of amplification forward pass collaborative communication method that mpsk signal is carried out network code, based on the system model (as shown in Figure 1) that communicates between two users of mutual relaying and the base station, adopt time-multiplexed transmission means, and the hypothesis channel is a Rayleigh channel, as shown in Figure 2, may further comprise the steps:
Step 1: at time slot 1, adopt the signal of coded data after the MPSK modulation of conventional transmitted power broadcasting user 1 self by user 1, differentiation is detected to the user's 1 that receives signal in user 2 and base station;
Step 2: at time slot 2, adopt the signal of coded data after the MPSK modulation of conventional transmitted power broadcasting user 2 self by user 2, differentiation is detected to the user's 2 that receives signal in user 1 and base station;
Step 3: by the good and bad result of base station by descending control signaling channel feedback two up channel signal to noise ratios;
Step 4: at time slot 3, adopt the power that surpasses conventional transmitted power to send the data of network code by the higher user of channel signal to noise ratio, Combined Treatment is carried out to 3 received signals of time slot in the base station, finally obtains user 1 and user's 2 coded data.
In the such scheme: 1) the described MPSK modulation system of step 1 and step 2 is a kind of MPSK modulation system based on the constellation point mapping mode of justifying the territory; 2) process of network code described in the step 4 is that the product calculation that adopts user 1 and user's 2 coded data to carry out analog domain replaces the XOR of digital signal in the common network code to realize; 3) Combined Treatment described in the step 4 is the base station obtains user 1 and user's 2 coded data after carrying out Maximum Likelihood Detection, demodulation to 3 received signals of time slot a detected value.
What the present invention proposed carries out the amplification forward pass collaborative communication method of network code to mpsk signal, if when mpsk signal wherein is bpsk signal, described Maximum Likelihood Detection process is a kind of approximate Maximum Likelihood Detection process, and concrete grammar is:
At first be defined as follows: x
1The data that [n] expression user 1 sends; x
2The data that [n] expression user 2 sends; y
1The signal that [n] expression base station receives at time slot 1; y
2The signal that [n] expression base station receives at time slot 2; y
3The signal that [n] expression base station receives at time slot 3;
The expression base station is at the posterior probability log-likelihood ratio of time slot 1 received signal;
The expression base station is at the posterior probability log-likelihood ratio of time slot 2 received signals;
The expression base station is at the posterior probability log-likelihood ratio of time slot 3 received signals; Pr (x[n]=+ 1) represent that transmit leg sends the prior probability of the data "+1 " after encoding, modulating; Pr (x[n]=-1) expression sends the prior probability of the data " 1 " after coding, the modulation;
Because statistics goes up prior probability
To x
1The Maximum Likelihood Detection value of [n]
(being the maximum a posteriori probability detected value) is:
To x
2The Maximum Likelihood Detection value of [n]
(being the maximum a posteriori probability detected value) is:
Therefrom as can be seen, adopt traditional maximum likelihood detection method to calculate x
1[n], x
2Need carry out complicated exponent arithmetic during the detected value of [n].The present invention proposes the lower approximate Maximum Likelihood Detection of a kind of complexity (Approximate Maximum Likelihood, AML) method.Consider that in the Turbo coding Max-Log-MAP decoding algorithm is used
Can reach the compromise of a kind of good complexity and performance.Can obtain approximate maximum likelihood detection method: to x
1The Maximum Likelihood Detection value of [n]
To x
2The Maximum Likelihood Detection value of [n]
In emulation, adopt smooth Rayleigh fading channel.Fig. 4 and Fig. 5 are AF-NC and non-collaborative bit error rate emulation and numerical result.Each link average signal-to-noise ratio equates in Fig. 4, and abscissa value is
Abscissa value is in Fig. 5
Frame length is 256 in the emulation, adopts the BPSK modulation.The bit error rate performance simulation result of AF-NC when Fig. 6 modulates for adopting 4PSK and 8PSK, abscissa value is among the figure
In emulation, in full accord when transfer resource distribution and simulated conditions and BPSK method.
Claims (5)
1. amplification forward pass collaborative communication method that mpsk signal is carried out network code, based on the system model that communicates between two users of mutual relaying and the base station, adopt time-multiplexed transmission means, and suppose that channel is a Rayleigh channel, may further comprise the steps:
Step 1: at time slot 1, adopt the signal of coded data after the MPSK modulation of conventional transmitted power broadcasting user 1 self by user 1, differentiation is detected to the user's 1 that receives signal in user 2 and base station;
Step 2: at time slot 2, adopt the signal of coded data after the MPSK modulation of conventional transmitted power broadcasting user 2 self by user 2, differentiation is detected to the user's 2 that receives signal in user 1 and base station;
Step 3: by the good and bad result of base station by descending control signaling channel feedback two up channel signal to noise ratios;
Step 4: at time slot 3, adopt the power that surpasses conventional transmitted power to send the data of network code by the higher user of channel signal to noise ratio, Combined Treatment is carried out to 3 received signals of time slot in the base station, finally obtains user 1 and user's 2 coded data.
2. according to claim 1 mpsk signal is carried out the amplification forward pass collaborative communication method of network code, it is characterized in that, the described MPSK modulation system of step 1 and step 2 is a kind of MPSK modulation system of the constellation point mapping mode based on the circle territory.
3. according to claim 1 mpsk signal is carried out the amplification forward pass collaborative communication method of network code, it is characterized in that network code described in the step 4 is the product calculation that user 1 and user's 2 coded data is carried out analog domain.
4. the amplification forward pass collaborative communication method that mpsk signal is carried out network code according to claim 1, it is characterized in that Combined Treatment described in the step 4 is the base station obtains user 1 and user's 2 coded data after carrying out Maximum Likelihood Detection, demodulation to 33 received signals of time slot a detected value.
5. according to claim 4 mpsk signal is carried out the amplification forward pass collaborative communication method of network code, it is characterized in that when mpsk signal was bpsk signal, described Maximum Likelihood Detection process was a kind of approximate Maximum Likelihood Detection process, concrete grammar is:
At first be defined as follows: x
1The data that [n] expression user 1 sends; x
2The data that [n] expression user 2 sends; y
1The signal that [n] expression base station receives at time slot 1; y
2The signal that [n] expression base station receives at time slot 2; y
3The signal that [n] expression base station receives at time slot 3;
The expression base station is at the posterior probability log-likelihood ratio of time slot 1 received signal;
The expression base station is at the posterior probability log-likelihood ratio of time slot 2 received signals;
The expression base station is at the posterior probability log-likelihood ratio of time slot 3 received signals; Pr (x[n]=+ 1) represent that transmit leg sends the prior probability of the data "+1 " after encoding, modulating; Pr (x[n]=-1) expression sends the prior probability of the data " 1 " after coding, the modulation;
To x
1The Maximum Likelihood Detection value of [n]
To x
2The Maximum Likelihood Detection value of [n]
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 201010531380 CN101977096B (en) | 2010-11-04 | 2010-11-04 | Amplify-and-forward (AF) cooperative communication method for performing network coding on MPSK signal |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 201010531380 CN101977096B (en) | 2010-11-04 | 2010-11-04 | Amplify-and-forward (AF) cooperative communication method for performing network coding on MPSK signal |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN101977096A true CN101977096A (en) | 2011-02-16 |
| CN101977096B CN101977096B (en) | 2013-05-08 |
Family
ID=43576947
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN 201010531380 Expired - Fee Related CN101977096B (en) | 2010-11-04 | 2010-11-04 | Amplify-and-forward (AF) cooperative communication method for performing network coding on MPSK signal |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN101977096B (en) |
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103199959A (en) * | 2013-04-12 | 2013-07-10 | 南京邮电大学 | Network coding method in collaborative communication |
| CN103368692A (en) * | 2013-07-03 | 2013-10-23 | 西安交通大学 | Self-adaption variable-time slot analog network coding strategy in two-way relay system |
| WO2016179934A1 (en) * | 2015-05-14 | 2016-11-17 | 中兴通讯股份有限公司 | Data transmission method and node |
| CN106899376A (en) * | 2015-12-17 | 2017-06-27 | 中国航天科工集团八五研究所 | The non-coherent detection methods of physical-layer network coding continuous phase modulated signal |
| CN108924779A (en) * | 2018-06-07 | 2018-11-30 | 天津大学 | A kind of multi-hop compression coding forwarding data transmission method |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101572654A (en) * | 2008-04-30 | 2009-11-04 | 华为技术有限公司 | Method and equipment for resource allocation |
| CN101702830A (en) * | 2009-10-28 | 2010-05-05 | 北京邮电大学 | Method for transmitting network coding user collaborative matching in wireless relay system |
| EP2202894A1 (en) * | 2008-12-23 | 2010-06-30 | NTT DoCoMo, Inc. | Relay station for a mobile communication system |
| CN101848060A (en) * | 2010-05-12 | 2010-09-29 | 中国科学技术大学 | Self-adaptive cooperation relay method through network coding |
-
2010
- 2010-11-04 CN CN 201010531380 patent/CN101977096B/en not_active Expired - Fee Related
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101572654A (en) * | 2008-04-30 | 2009-11-04 | 华为技术有限公司 | Method and equipment for resource allocation |
| EP2202894A1 (en) * | 2008-12-23 | 2010-06-30 | NTT DoCoMo, Inc. | Relay station for a mobile communication system |
| CN101702830A (en) * | 2009-10-28 | 2010-05-05 | 北京邮电大学 | Method for transmitting network coding user collaborative matching in wireless relay system |
| CN101848060A (en) * | 2010-05-12 | 2010-09-29 | 中国科学技术大学 | Self-adaptive cooperation relay method through network coding |
Cited By (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103199959A (en) * | 2013-04-12 | 2013-07-10 | 南京邮电大学 | Network coding method in collaborative communication |
| CN103199959B (en) * | 2013-04-12 | 2016-08-03 | 南京邮电大学 | A kind of network coding method in collaboration communication |
| CN103368692A (en) * | 2013-07-03 | 2013-10-23 | 西安交通大学 | Self-adaption variable-time slot analog network coding strategy in two-way relay system |
| CN103368692B (en) * | 2013-07-03 | 2016-06-08 | 西安交通大学 | Adaptive strain time slot analog network coding strategy in a kind of bidirectional relay system |
| WO2016179934A1 (en) * | 2015-05-14 | 2016-11-17 | 中兴通讯股份有限公司 | Data transmission method and node |
| CN106304197A (en) * | 2015-05-14 | 2017-01-04 | 中兴通讯股份有限公司 | A kind of data transmission method and node |
| CN106899376A (en) * | 2015-12-17 | 2017-06-27 | 中国航天科工集团八五研究所 | The non-coherent detection methods of physical-layer network coding continuous phase modulated signal |
| CN106899376B (en) * | 2015-12-17 | 2019-12-27 | 中国航天科工集团八五一一研究所 | Non-coherent detection method for physical layer network coding continuous phase modulation signal |
| CN108924779A (en) * | 2018-06-07 | 2018-11-30 | 天津大学 | A kind of multi-hop compression coding forwarding data transmission method |
Also Published As
| Publication number | Publication date |
|---|---|
| CN101977096B (en) | 2013-05-08 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN101515842B (en) | Method for transmitting partial cooperative information based on fountain coding | |
| CN105245269B (en) | Letter energy simultaneous interpretation relay transmission method in safety of physical layer communication | |
| CN101990324B (en) | Method for actively selecting user terminal in relay system and base station | |
| CN101860873A (en) | Distributed relay selection method based on cross-layer information exchange | |
| CN101977096B (en) | Amplify-and-forward (AF) cooperative communication method for performing network coding on MPSK signal | |
| CN102545992B (en) | Optimal relay selection and power distribution method of DF (decode-forward) relay system | |
| CN101394255A (en) | Two-user collaboration communication method in multi-user wireless network | |
| CN101826935B (en) | Low-density parity check code-based relay cooperative transmission method | |
| CN102811120A (en) | System and method for controlling both-way relay HARQ (hybrid automatic repeat request) based on network coding | |
| CN101888358A (en) | Transmission method for reducing computational complexity of two-way relay nodes based on network coding | |
| CN101848060A (en) | Self-adaptive cooperation relay method through network coding | |
| CN103138892B (en) | Self-adaption relay communication method based on ladder modulation | |
| CN104883240B (en) | The time division broadcast method of joint difference multiplication forwarding and selection combining | |
| CN101483458B (en) | Information interactive combining method in collaboration multi-point receiving | |
| CN105553536A (en) | Overlapped code division multiplexing hybrid forwarding cooperative communication method | |
| CN101383681A (en) | Encoding and decoding method for resisting asynchronous differential space time block code | |
| CN105554813B (en) | It is a kind of in data transmission method of the wireless relay system based on Random Maps code | |
| CN102487315B (en) | Multi-source multi-relay cooperation communication method, communication equipment and cooperation communication system | |
| CN102857323A (en) | Amplification and transmission coordination based network coding method | |
| CN102334379B (en) | Method and apparatus for associated processing in relay station and corresponding processing in base station | |
| CN104243386A (en) | Additional channel information transmission method for multi-carrier communication system | |
| Hidayati | Performance of best relay selection in single relay selection scheme with network coding | |
| CN105704079A (en) | Physical layer network coding (PLNC)-based combined subcarrier suppression and relay selection method in bidirectional orthogonal frequency division multiplexing (OFDM) multi-relay system | |
| CN103051427B (en) | Duplex wireless relay communication method based on network coding | |
| CN105577247B (en) | Collaboration communication method is overlapped when a kind of serial empty |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| CF01 | Termination of patent right due to non-payment of annual fee |
Granted publication date: 20130508 Termination date: 20141104 |
|
| EXPY | Termination of patent right or utility model |