無線協(xié)作通信系統(tǒng)中分集編碼與檢測技術(shù)研究
發(fā)布時間：2019-05-08 08:32
【摘要】：新一代移動通信網(wǎng)絡(luò)系統(tǒng)對通信速率、通信可靠性提出了更高要求，無線協(xié)作通信技術(shù)由于具備多天線系統(tǒng)的特性，能夠有效利用多徑傳播來滿足這些性能要求，故而受到廣泛關(guān)注。無線協(xié)作通信技術(shù)的基本思想是通過多個單天線用戶終端，構(gòu)成虛擬天線陣列以協(xié)助信源與信宿的通信。該技術(shù)通過構(gòu)建多用戶協(xié)作的分集編碼，有助于提高信道容量、獲取分集增益、共享鏈路資源�；诖�，本研究圍繞無線協(xié)作通信系統(tǒng)中的分集編碼技術(shù)，從正交轉(zhuǎn)發(fā)協(xié)議、非正交轉(zhuǎn)發(fā)協(xié)議、兩路中繼信道轉(zhuǎn)發(fā)協(xié)議等方面探究了無線協(xié)作分集編碼技術(shù)的實質(zhì)問題；同時，針對這些問題提出了一些新的分集編碼設(shè)計方法和信號檢測方法、并進行了相關(guān)性能分析。具體而言，本研究的主要結(jié)論如下： 1.針對現(xiàn)有分布式空時編碼和分布式空頻編碼應(yīng)用于高速車載寬帶通信系統(tǒng)存在的不足，利用高速車載終端與車外基站通信時信道的多徑時變特性，提出可適用于此通信場景的無線協(xié)作通信系統(tǒng)模型及相應(yīng)通信節(jié)點間的信道模型。在此基礎(chǔ)上，提出一種分布式空時頻編碼設(shè)計方法，其可在通信速率無損耗的前提下，獲得此通信場景中潛在的協(xié)作分集、時間分集和頻率分集增益。同時，針對低信噪比時提出的分布式空時頻編碼較分布式空頻編碼誤碼性能較差的問題，提出了這兩種編碼方法結(jié)合使用的切換策略。 2.針對快衰落、多載波、頻率選擇性衰落中信道估計困難、開銷較大的問題，提出一種差分酉調(diào)制多中繼協(xié)作空頻編碼。理論分析和仿真結(jié)果驗證了提出的方法可獲得完全的協(xié)作和頻率分集增益。為進一步優(yōu)化提出編碼方法的誤碼性能，以接收信號合并信噪比最大為準則，推導(dǎo)了接收信號分集合并的均值信噪比解析式，并由此分析了中繼個數(shù)、中繼位置、合并系數(shù)等參數(shù)對信噪比取值的影響。由于中繼個數(shù)、中繼位置的優(yōu)化解在區(qū)間的邊界點上，為使優(yōu)化工作有實際意義，確定了常用的中繼個數(shù)、中繼位置，并在此基礎(chǔ)上得到了功率分配因子及最大比合并因子比值的理論優(yōu)化解。仿真實驗結(jié)果驗證了理論優(yōu)化解的有效性和多參數(shù)優(yōu)化的優(yōu)越性。 3.針對解碼轉(zhuǎn)發(fā)方式下差分網(wǎng)絡(luò)編碼對應(yīng)的中繼差分檢測復(fù)雜度高、差分網(wǎng)絡(luò)編碼環(huán)節(jié)繁雜的問題，提出一種復(fù)數(shù)域符號相乘的差分網(wǎng)絡(luò)編碼，立足提出的差分網(wǎng)絡(luò)編碼思想，通過構(gòu)建的檢測方法一，中繼可檢測得到兩路終端的差分分組編碼，通過構(gòu)建的檢測方法二，中繼可檢測得到差分網(wǎng)絡(luò)編碼，無需檢測兩路發(fā)送信息分組，中繼的檢測復(fù)雜度顯著降低、處理環(huán)節(jié)明顯減少。同時，為了獲取高階分集增益，基于提出的復(fù)數(shù)域符號相乘的差分網(wǎng)絡(luò)編碼思想，提出了多中繼協(xié)作的隨機差分空時網(wǎng)絡(luò)編碼，可獲得的協(xié)作分集階數(shù)為激活中繼個數(shù)。 4.在多子載波、頻率選擇性衰落、兩路中繼轉(zhuǎn)發(fā)信道中，提出一種多中繼協(xié)作的基于AF-CDC-OFDM的差分網(wǎng)絡(luò)編碼方法。通過多個協(xié)作中繼的分布式循環(huán)延時編碼和功率放大處理，兩路終端發(fā)送的差分編碼分組可獲得完全的協(xié)作分集和頻率分集增益。兩路終端在檢測對方的發(fā)送信號之前需要消除自身干擾信號，為此，提出了一種基于相關(guān)統(tǒng)計的自干擾估計和消除方法。仿真實驗結(jié)果驗證了提出的分集編碼方法和自干擾消除方法的有效性。 5.在非正交轉(zhuǎn)發(fā)協(xié)議中應(yīng)用機會策略可獲得高階分集增益。為了研究瑞利衰落信道中非正交選擇放大轉(zhuǎn)發(fā)協(xié)議和非正交選擇譯碼轉(zhuǎn)發(fā)協(xié)議的遍歷容量，推導(dǎo)了兩種轉(zhuǎn)發(fā)協(xié)議下遍歷容量界的閉式表達式，，通過仿真得到了兩種協(xié)議在不同備選中繼個數(shù)時的遍歷容量。仿真結(jié)果表明：兩種協(xié)議的遍歷容量隨備選中繼個數(shù)的增加而改善；相對而言，低信噪比時非正交選擇放大轉(zhuǎn)發(fā)協(xié)議的遍歷容量較大，高信噪比時非正交選擇譯碼轉(zhuǎn)發(fā)協(xié)議的遍歷容量較大。 6.針對非正交轉(zhuǎn)發(fā)協(xié)議中信號聯(lián)合似然檢測時間復(fù)雜度高、檢測性能差的問題，提出了一種新的干擾消除快速檢測方法，該方法通過最大比合并使強信號幀獲得二階分集增益并先行檢測，然后，以檢測值消除對弱信號幀的干擾后再檢測弱信號幀。理論分析表明，提出的方法可以有效降低檢測時間復(fù)雜度。此外，通過仿真驗證了新檢測方法的誤比特性能有明顯改善，仿真結(jié)果表明新方法誤比特性能的仿真與理論值在高信噪比時趨于一致。
[Abstract]:The new generation mobile communication network system has higher requirements for communication rate and communication reliability, and the wireless cooperative communication technology can effectively utilize the multi-path propagation to meet the performance requirements due to the characteristics of the multi-antenna system, thus being widely concerned. The basic idea of the wireless cooperative communication technology is to form a virtual antenna array through a plurality of single-antenna user terminals to assist the communication between the source and the sink. The technology can improve the channel capacity, acquire the diversity gain and share the link resources by building the diversity coding of the multi-user cooperation. Based on this, the present study probes into the merits of the wireless cooperative diversity coding technology from the aspects of the orthogonal forward protocol, the non-orthogonal forward protocol, the two-way relay channel forwarding protocol, and the like in the wireless cooperative communication system, and meanwhile, In this paper, some new methods of diversity coding design and signal detection are put forward, and the relevant performance analysis is carried out. Specifically, the main conclusions of this study are as follows: 1. Aiming at the defects that the existing distributed space-time coding and the distributed space-frequency coding are applied to the high-speed on-board broadband communication system, the multipath time-variant of the channel when the high-speed vehicle-mounted terminal is in communication with the outside base station the invention provides a wireless cooperative communication system model applicable to the communication scene and a channel mode among the corresponding communication nodes, On the basis of this, a distributed null time-frequency coding design method is proposed, which can obtain the potential cooperative diversity, time diversity and frequency diversity in the communication scene on the premise of no loss of communication rate. In the meantime, at the same time, in the case of the low signal-to-noise ratio, the distributed null time-frequency coding is less than that of the distributed null-frequency code, and the switching scheme used in combination with the two coding methods is put forward. In ord to solve that problem of difficulty in channel estimation and high overhead in fast fading, multi-carrier and frequency selective fading, a kind of differential coherent modulation multi-relay cooperation is proposed. The theoretical analysis and the simulation results verify that the proposed method can obtain full cooperation and frequency division In order to further optimize the error-error performance of the proposed coding method, the signal-to-noise ratio (SNR) of the received signal is derived, and the signal-to-noise ratio (SNR) of the received signal is analyzed, and the value of the signal-to-noise ratio (SNR) of the relay number, the relay location, the merging coefficient and the like is analyzed. The influence of the relay number and the relay position is the boundary point of the interval. In order to make the optimization work practical, the common relay number and the relay position are determined, and the theory of the ratio of the power distribution factor and the maximum ratio combining factor is obtained. The results of the simulation show the effectiveness of the theoretical optimization solution and the multi-parameter optimization. 3. The differential network coding corresponding to the differential network coding in the decoding and forwarding mode is high, the complexity of the differential network coding links is complicated, a differential network coding with a plurality of domain symbols is proposed, the proposed differential network coding method is based on the proposed differential network coding method, the detection method 1, the relay can detect the differential packet code of the two terminals, the detection method 2 and the relay can be detected to obtain the differential network coding, the detection complexity of the relay is obviously reduced, and the processing ring in addition, in ord to obtain high-order diversity gain, a multi-relay cooperative random differential space-time network coding is put forward in order to obtain high-order diversity gain, number of live trunks.4. In multi-carrier, frequency selective fading, two-way relay forwarding channels, a multi-relay cooperative AF-CDC-OFDM based difference is proposed by means of distributed cyclic delay coding and power amplification processing of a plurality of cooperative relays, the differential coding packets sent by the two terminals can obtain full cooperation diversity, and the two-way terminal needs to eliminate the self-interference signal before the transmission signal of the other side is detected, The results of the simulation show the proposed diversity coding method and the self-interference cancellation method. the effectiveness of the method.5. Apply the opportunity policy in a non-orthogonal forwarding protocol In ord to study that traversal capacity of the non-orthogonal selective amplify and forward protocol and the non-orthogonal selective decode and forward protocol in the Rayleigh fading channel, the closed expression of the traverse capacity boundary under two forward protocols is derived. The simulation results show that the ergodic capacity of the two protocols is improved with the increase of the number of alternative relay. In order to solve the problem of high complexity and poor detection performance of signal joint-likelihood detection in non-orthogonal forward protocol, a new method for fast detection of interference cancellation is proposed. the set gain is first detected and then the weak signal frame is eliminated with a detection value and the weak signal frame is detected after the interference of the interference, the theoretical analysis shows that the proposed method can in addition, that error bit performance of the new detection method is obviously improve by simulation, and the simulation result shows that the simulation and the theory of the error bit performance of the new method
【學(xué)位授予單位】：西安電子科技大學(xué)
【學(xué)位級別】：博士
【學(xué)位授予年份】：2014
【分類號】：TN929.5
本文編號：2471757
[Abstract]:The new generation mobile communication network system has higher requirements for communication rate and communication reliability, and the wireless cooperative communication technology can effectively utilize the multi-path propagation to meet the performance requirements due to the characteristics of the multi-antenna system, thus being widely concerned. The basic idea of the wireless cooperative communication technology is to form a virtual antenna array through a plurality of single-antenna user terminals to assist the communication between the source and the sink. The technology can improve the channel capacity, acquire the diversity gain and share the link resources by building the diversity coding of the multi-user cooperation. Based on this, the present study probes into the merits of the wireless cooperative diversity coding technology from the aspects of the orthogonal forward protocol, the non-orthogonal forward protocol, the two-way relay channel forwarding protocol, and the like in the wireless cooperative communication system, and meanwhile, In this paper, some new methods of diversity coding design and signal detection are put forward, and the relevant performance analysis is carried out. Specifically, the main conclusions of this study are as follows: 1. Aiming at the defects that the existing distributed space-time coding and the distributed space-frequency coding are applied to the high-speed on-board broadband communication system, the multipath time-variant of the channel when the high-speed vehicle-mounted terminal is in communication with the outside base station the invention provides a wireless cooperative communication system model applicable to the communication scene and a channel mode among the corresponding communication nodes, On the basis of this, a distributed null time-frequency coding design method is proposed, which can obtain the potential cooperative diversity, time diversity and frequency diversity in the communication scene on the premise of no loss of communication rate. In the meantime, at the same time, in the case of the low signal-to-noise ratio, the distributed null time-frequency coding is less than that of the distributed null-frequency code, and the switching scheme used in combination with the two coding methods is put forward. In ord to solve that problem of difficulty in channel estimation and high overhead in fast fading, multi-carrier and frequency selective fading, a kind of differential coherent modulation multi-relay cooperation is proposed. The theoretical analysis and the simulation results verify that the proposed method can obtain full cooperation and frequency division In order to further optimize the error-error performance of the proposed coding method, the signal-to-noise ratio (SNR) of the received signal is derived, and the signal-to-noise ratio (SNR) of the received signal is analyzed, and the value of the signal-to-noise ratio (SNR) of the relay number, the relay location, the merging coefficient and the like is analyzed. The influence of the relay number and the relay position is the boundary point of the interval. In order to make the optimization work practical, the common relay number and the relay position are determined, and the theory of the ratio of the power distribution factor and the maximum ratio combining factor is obtained. The results of the simulation show the effectiveness of the theoretical optimization solution and the multi-parameter optimization. 3. The differential network coding corresponding to the differential network coding in the decoding and forwarding mode is high, the complexity of the differential network coding links is complicated, a differential network coding with a plurality of domain symbols is proposed, the proposed differential network coding method is based on the proposed differential network coding method, the detection method 1, the relay can detect the differential packet code of the two terminals, the detection method 2 and the relay can be detected to obtain the differential network coding, the detection complexity of the relay is obviously reduced, and the processing ring in addition, in ord to obtain high-order diversity gain, a multi-relay cooperative random differential space-time network coding is put forward in order to obtain high-order diversity gain, number of live trunks.4. In multi-carrier, frequency selective fading, two-way relay forwarding channels, a multi-relay cooperative AF-CDC-OFDM based difference is proposed by means of distributed cyclic delay coding and power amplification processing of a plurality of cooperative relays, the differential coding packets sent by the two terminals can obtain full cooperation diversity, and the two-way terminal needs to eliminate the self-interference signal before the transmission signal of the other side is detected, The results of the simulation show the proposed diversity coding method and the self-interference cancellation method. the effectiveness of the method.5. Apply the opportunity policy in a non-orthogonal forwarding protocol In ord to study that traversal capacity of the non-orthogonal selective amplify and forward protocol and the non-orthogonal selective decode and forward protocol in the Rayleigh fading channel, the closed expression of the traverse capacity boundary under two forward protocols is derived. The simulation results show that the ergodic capacity of the two protocols is improved with the increase of the number of alternative relay. In order to solve the problem of high complexity and poor detection performance of signal joint-likelihood detection in non-orthogonal forward protocol, a new method for fast detection of interference cancellation is proposed. the set gain is first detected and then the weak signal frame is eliminated with a detection value and the weak signal frame is detected after the interference of the interference, the theoretical analysis shows that the proposed method can in addition, that error bit performance of the new detection method is obviously improve by simulation, and the simulation result shows that the simulation and the theory of the error bit performance of the new method
【學(xué)位授予單位】：西安電子科技大學(xué)
【學(xué)位級別】：博士
【學(xué)位授予年份】：2014
【分類號】：TN929.5
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相關(guān)期刊論文 前3條
1 趙賢敬;鄭寶玉;;一種協(xié)同分集方案的誤碼性能分析[J];電子學(xué)報;2007年07期
2 羅濤;李祥明;王健康;樂光新;;基于空時分組編碼的協(xié)同通信系統(tǒng)性能的研究[J];電子與信息學(xué)報;2007年09期
3 張勇;徐友云;蔡躍明;;非正交選擇譯碼轉(zhuǎn)發(fā)協(xié)同[J];電子與信息學(xué)報;2008年09期
本文編號：2471757
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