Logical Superposition Coded Video Multicast/Broadcast

Abstract

Joint source and channel coding (JSCC) has been widely reported for its superb capability in mitigating the legacy channel/user diversity problem in the wireless multicast/broadcast scenario, where the successive refined source information is manipulatively mapped with superimposed channel symbols via superposition coding (SPC). However, the use of SPC involves in additional hardware in the physical layer, which may not be in compliance in most standard equipments and protocols. This paper introduces a novel framework of logical superposition coded (L-SPC) modulation for multicast/broadcast of successive refined source via the JSCC approach. The framework is characterized by completely software-based logical SPC modulation at the sender, where the modulated signal is generated by mapping successively refined information bits onto a single signal constellation. At the receiving end, the proposed framework only needs simple modifications in the MAC layer software, while the required demodulation schemes are completely compatible with the standard ones with uniform constellation. Generalized formulations on symbol error rate are derived for performance evaluation and comparisons with the conventional hardwarebased approach for both 2-layer and 3-layer cases.

Subgrouping‐based multicast transmission over high‐throughput satellite systems with beam cooperation

“…where is a factor depending on the specific system at hand Remarkably, according to Equation (17), the determination of 1 and 2 is critical to the scheme on account of their influence on system performance and the design of the modulation constellation. 36,37 For a multicast group, 1 can be set as min…”

“…As an application of superposition coding, HM utilizes a specific bit‐to‐symbol mapping to achieve multirate transmission 35 . However, HM has a high hardware complexity 36 . Scalable modulation (SM) can make the design of HM by constellation mapping and thus reduce the complexity 37 .…”

“…Remarkably, according to Equation (17), the determination of γ 1 and γ 2 is critical to the scheme on account of their influence on system performance and the design of the modulation constellation 36,37 . For a multicast group, γ 1 can be set as to guarantee that all the multicast members can receive the multicast data.…”

Delivery Design for Coded Caching Over Wireless Multicast Networks

“…Then, each X k is mapped to a codeword X 1:n k 8 of length n, which is chosen from the k-th codebook [35]. Afterwards, all K codewords will be superposed and transmitted, just as recommended in [39], [40]. Due to |h Because we assume SPC and SIC, the delivery framework can be equivalently illustrated by Fig.…”