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Millimeter wave communication is a main solution for the high speed backhaul and ultra-high speed access transmission. This paper presented the interface-aware LDPC codes in the millimeter-wave system to support highspeed Ethernet interfaces and reduce the conversion delay. Considering constraints of the encoded codeword length of 1 G to 100 G Ethernet physical layer, LDPC (196, 120), LDPC (588, 528),...
Lattice network coding is recently proposed as a practical implementation of Nazer-Gastpar's compute-and-forward relaying strategy. Previous investigation of lattice network coding is mainly over finite fields. In this paper, we extend lattice network coding from finite fields to finite rings. In addition to having its own theoretical interest, this extension provides an alternative viewpoint of Nazer-Gastpar's...
We propose a half-duplex cooperative scheme for a discrete memoryless channel (DMC) consisting of two users communicating with one destination. The half-duplex constraint is satisfied by performing the communication over 3 time slots with variable durations in each code block. Each user alternatively transmits and receives during the first 2 time slots, then both of them transmit during the last one...
The creation of Ultra-Wideband (UWB) radio platform has allowed the development of high bit-rate Wireless-USB offering High Definition video streaming. Quadrature Phase Shift Keying (QPSK) and Dual Carrier Modulation (DCM) are the current modulation schemes used for Multiband Orthogonal Frequency Division Multiplexing (MB-OFDM) in the ECMA-368 defined UWB radio platform. ECMA-368 offers up to 480...
The performance of a wireless system depends on the wireless channel as well as the algorithms used in the transceiver pipelines. Because physical phenomena affect transceiver pipelines in difficult to predict ways, detailed simulation of the entire transceiver system is needed to evaluate even a single processing block. Further, some protocol validations require simulation of rare events (say, 1...
Network coding has been studied as a solution to mitigate traffic concentration at a bottleneck node in wireless multihop networks. When network coding is applied to a unicast flow, the decoding nodes overhear packet transmissions, receive all packets which are headed for not only themselves but also the other nodes, and store them. The reception of undesired packets is, however, unreliable, and this...
We consider the performance of small-scale heterogeneous cooperative networks in which some nodes can transmit and/or receive using channels not available to other nodes, i.e., multimodal communication networks. As an example, we assume the presence of an additional wired channel in a conventional diamond relay network operating under the Laneman protocol, and we find analytical expressions for outage...
Streaming degradable content (such as video or audio) over a wireless channel presents new challenges to modern digital design, which was founded on the separation theorem of Shannon theory. Joint source-channel coding (JSCC) has recently received increasing interest to address the varying nature of the wireless channel conditions (under mobility or multicast). The conventional approach to JSCC which...
We propose two scheduling protocols which are applicable to two-hop relay networks based on mobile WiMAX system: the first protocol adopts a persistent scheduling (PS) scheme in both hops, called the PS-PS protocol, while the second protocol adopts the PS scheme only in the first hop and the dynamic scheduling (DS) scheme in the second hop, called the PS-DS protocol. We optimize the above two protocols...
Cooperation among nodes in a network provides spatial diversity as well as it enhances the system's overall capacity and coverage. However the benefits provided by such systems depends on the level of cooperation (based on the relay information quality) and on the coordination among nodes. One way of achieving proper coordination is through the use of feedback channels. An implicit feedback channel...
This paper considers the problem of uplink scheduling in wireless networks supporting successive interference cancellation (SIC) at the physical layer. By allowing concurrent interfering transmissions, SIC enables multi-packet reception at the receiver resulting in increased network throughput. Specifically, we consider maximum throughput scheduling and proportional fair scheduling problems and study...
After the initial interest caused by appearance of turbo-codes in 1993, special attention to the hardware implementation has led to many different modified algorithms for MAP decoders. The original MAP algorithm suffers from serious drawbacks in its hardware implementation. To overcome this disadvantage, Max-Log-MAP and Log-MAP algorithms have been proposed to reduce the complexity. Recently an improved...
We evaluate the outage probability and the spectral efficiency of cooperative multi-hop networks, where L relay nodes are placed at each hop and an MDS (Maximum Distance Separable) code of coding rate 1/L is employed at the link-layer. A codeword of the MDS code is partitioned into L blocks. When each relay node receives two or more codeword blocks of the MDS code, it aggregates the blocks, corrects...
This paper presents a blind soft-output modulation decoder for signals transmitted wirelessly using any constellation configuration. The receiver algorithm operates by classifying the received symbols into probabilistically alike clusters which are ultimately used to estimate the underlying modulation constellation points and also soft information about the received signal.
Mobile WiMAX can provide high-speed wireless access to mobile users. It also supports applications and services with diverse QoS (Quality of Service) requirements. However, it does not guarantee media quality for multimedia streaming services using scalable video coding schemes, because it does not consider essential characteristics of video coding techniques and network congestion. To solve this...
In this paper, we propose a wireless transmission of JPEG 2000 compressed video. The proposed system employs the next generation wireless LAN system based on IEEE802.11ac specification. It reaches more than 33 meter propagation distance by using 80MHz of bandwidth on the 5GHz band. In this system, video data is compressed by JPEG 2000 with error resilience tools. These tools improve error performance...
We propose a physical layer approach to detect the relay node that injects false data or adds channel errors into the network encoder in multiple access relay networks. The misbehaving relay is detected by using the maximum a posteriori (MAP) detection rule which is optimal in the sense of minimizing the probability of incorrect decision (false alarm and miss detection). The proposed scheme does not...
This paper presents an improved feedback-assisted low complexity WZVC scheme. The performance of this scheme is improved by two enhancements: an improved mode-based key frame encoding and a 3DRS-assisted (three-dimensional recursive search assisted) motion estimation algorithm for WZ encoding. Experimental results show that our coding scheme can achieve significant gain compared to state-of-the-art...
In order to support an acceptable quality-of-service (QoS) in mobile wireless communication systems in terms of physical layer metrics, Serial Concatenated Convolutional Codes (SCCCs) are emerging as a strong candidate, promising remarkable coding gains with reasonable decoding complexities. This work addresses the performance evaluation of SCCCs over aeronautical channels, based on a ground-to-air...
A new approach for the approximation of the channel log-likelihood ratio (LLR) for wireless channels based on Taylor series is proposed. The approximation is applied to the uncorrelated flat Rayleigh fading channel with unknown channel side information at the receiver. It is shown that the proposed approximation greatly simplifies the calculation of channel LLRs, and yet provides results almost identical...
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