Coding Schemes for the Two-Way Relay Channels
نویسنده
چکیده
In modern transmission networks, relay plays an important role for cooperative strategies. Several relaying strategies, such as decode-forward, compress-forward and amplify-forward, have been proposed for relay channels and networks. However, the capacity for the general relay channel and network is still unknown. In this thesis, we propose several relay schemes for different relay models. In the first part of the thesis, we propose novel partial decode-forward (PDF) schemes for the two-way relay channel with direct link. Different from pure decode-forward, each user divides its message into two parts and the relay decodes only one part of each. The relay then generates its codeword as a function of the two decoded parts and forwards to the two users. We propose PDF schemes for both the fulland half-duplex modes. Analysis and simulation show that if for one user, the direct link is stronger than the user-to-relay link, while for the other, the direct link is weaker, then PDF can achieve a rate region strictly larger than the time-shared region of pure decode-forward and direct transmission for both fulland half-duplex modes. The second part of the thesis is based on noisy network coding, which is recently proposed for the general multi-source network by Lim, Kim, El Gamal and Chung. This scheme builds on compress-forward (CF) relaying but involves three new ideas, namely no Wyner-Ziv binning, relaxed simultaneous decoding and message repetition. In this part, using the one-way and two-way relay channel as the underlining example, we analyze the impact of each of these ideas on the achievable rate region of relay networks. In the third part of the thesis, we propose two coding schemes combining decode-forward (DF) and noisy network coding (NNC) with different flavors. The first is a combined DFNNC scheme for the one-way relay channel which includes both DF and NNC as special cases by performing rate splitting, partial block Markov encoding and NNC. The second combines two different DF strategies and layered NNC for the two-way relay channel. Analysis and simulation show that both proposed schemes supersede each individual scheme and take full advantage of both DF and NNC.
منابع مشابه
Bounds for Multiple-Access Relay Channels with Feedback via Two-way Relay Channel
In this study, we introduce a new two-way relay channel and obtain an inner bound and an outer bound for the discrete and memoryless multiple access relay channels with receiver-source feedback via two-way relay channel in which end nodes exchange signals by a relay node. And we extend these results to the Gaussian case. By numerical computing, we show that our inner bound is the same with o...
متن کاملOn the Achievable Rate-Regions for the Gaussian Two-way Diamond Channels
In this channel,we study rate region of a Gaussian two-way diamond channel which operates in half-duplex mode. In this channel, two transceiver (TR) nodes exchange their messages with the help of two relay nodes. We consider a special case of the Gaussian two-way diamond channels which is called Compute-and-Forward Multiple Access Channel (CF-MAC). In the CF-MAC, the TR nodes transmit their mes...
متن کاملAchievable Rate Regions of Two-Way Relay Channels
With the fast development of communication networks, cooperative communication has been more widely used in many different fields, such as satellite networks, broadcast networks, internet and so on. Therefore relay channels have been playing a pivotal role since their definitions were proposed by Van-der Meulen. However, the general achievable rate region of a relay channel is still unknown whi...
متن کاملPower Allocation Strategies in Block-Fading Two-Way Relay Networks
This paper aims at investigating the superiority of power allocation strategies, based on calculus of variations in a point-to-point two-way relay-assisted channel incorporating the amplify and forward strategy. Single and multilayer coding strategies for two cases of having and not having the channel state information (CSI) at the transmitters are studied, respectively. Using the notion of cal...
متن کاملLinear Analog Network-Coded OFDM in Two-way Relay Channels
We study analog network-coded (ANC) orthogonal frequency division multiplexing (OFDM) in two-way relay channels and propose three linear analog network coding (LANC) schemes. Motivated by the fact that higher frequency diversity has been made available in the frequency-selective ANC two-way relay channels, the proposed LANC is applied to the frequencydomain OFDM signals with unitary matrices. T...
متن کامل