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Cooperative communications has emerged as an efficient realization of multiple input and multiple output (MIMO) systems. To reap the benefits of cooperative communications we follow the block-Markov code book structure. Recently a low cost and efficient operational implementation of block-Markov coding, using network coding, has been proposed. In this paper, we derive the closed form expression for...
In this paper, we propose a 4 K digital cinema transmission over 1.2 Gbps wireless LAN system. The proposed system employs the next generation wireless LAN system based on IEEE802.11ac task group. It reaches more than 33 meter propagation distance by using 80 MHz of bandwidth on 5 GHz band. In this system, a video data is compressed by JPEG 2000 with error resilience tools. These tools improve error...
In this paper, the structure of a trellis-coded 3-dimensional orthogonal frequency division multiplexing (3-D OFDM) is proposed and its error performance in additive white Gaussian channel is analyzed. We present the set-partitioning of a 3-D 8-ary constellation for trellis coding. As a result, the trellis-coded 3-D OFDM system has around 6 dB coding gain over an uncoded one when an 8-ary constellation...
There are a few core technologies to enable high-performance 4th generation (4G) broadband wireless communication system. A multiple input multiple output (MIMO) provides high-rate transmission through expended channels by multiple array antennas in both sender and receiver side. Also orthogonal frequency division multiplexing (OFDM) is well-known as the most appropriate technique for high data rate...
In this paper, the performance of a double binary turbo coded space time block code-ultra wide band (STBC-UWB) system is analyzed and simulated in multi-user environments. From the simulation results, it is demonstrated that the double binary turbo coding technique offers considerable coding gain with reasonable encoding and decoding complexity. It is confirmed that the double binary turbo coding...
We compare the performance of two real-time multimedia communication systems for quality versus end-to-end delay. We develop an analytical framework for comparison when the systems use a deterministic time-varying channel. Moreover, we assess their performance for the Gilbert-Elliott channel model which alternates between a good and a bad state with time durations that are exponentially distributed...
In a wireless sensor network, it is likely that the measurements of the sensors are correlated. Distributed source coding can be used to reduce transmission rate or mitigate the effects of the channel noise in the case of analog transmission. In this paper, we propose a novel scheme for implementing distributed source-channel coding based on analog mappings. We assume that an analog source is to be...
Network coding (NC) is an emerging technology area promising to increase the utilization of both wired and wireless networks. It can be seen as an extension to routing by allowing relay nodes to combine the information received from multiple links in the subsequent transmissions. NC was initially proposed in the context of multicast in wired networks where it was proven to achieve the maximum multicast...
Recent studies have determined the performance of TCH(n,k) (Tomlinson, Cercas, Hughes) codes in different environments, namely for mobile satellite channels for which TCH codes of small length n (e.g. 16) present some advantages when compared with TCH codes of higher length (e.g. 256). However, the correlation characteristics of TCH codes of small length present some peaks that deteriorate its performance...
Tailbiting convolutional codes will be used for several applications in new cellular mobile radio systems. This encoding method does not reset the encoder memory at the end of each data block, avoiding the overhead of the zero tail and improving the efficiency, especially when encoding short data blocks. Nevertheless, the absence of a known tail highly increases the complexity of the decoding process...
We present the e-outage capacity of incremental relaying at low signal-to-noise ratios (SNR) in a wireless cooperative network with slow Rayleigh fading channels. The relay performs decode-and-forward and repetition coding is employed in the network, which is optimal in the low SNR regime. We derive an expression on the optimal relay location that maximizes the e-outage capacity. It is shown that...
We propose a forwarding scheme by superposition coding for wireless relaying, in which a relay will not forward a message to a destination if the destination has successfully decoded the message directly from a source. In our scheme, flag signal and data signal are superimposed and transmitted by the source, and according to whether the flag signal has been successfully decoded by the relay, the relay...
Channel condition is considered an important issue that affects the performance in wireless networks. Link Adaptation techniques have been proposed to improve the degraded network performance by adjusting the design parameters, e.g. the modulation and coding schemes, in order to adopt the dynamically changing channel conditions. Furthermore, due to the advancement of the IEEE 802.11n standard, the...
Compared to conventional network coding, which must combine bit streams after they are decoded, the physical layer network coding (PNC) could make full use of electromagnetic (EM) waves arrived and combine bit stream at the physical layer. Because of this the system throughput could be improved. In this scheme we integrate PNC technique into wireless video transmission based on H.264 for relay channel...
Adaptive modulation and coding (AMC) is a powerful technique to enhance the link performance by adjusting the transmission power, channel coding rates and modulation levels according to channel state information. In order to efficiently utilize the AMC scheme, an accurate signal-to-noise ratio (SNR) value is normally required for determining the AMC level. In this paper, we propose a simple method...
Low utilization efficiency of spectrum, which is caused by fixed spectrum allocation scheme, is the bottleneck of wireless communication systems. Cognitive Radio (CR) is proposed to utilize the idle spectrum in an intelligent way while not interfering with primary users. For application of CR, the objective is the optimization of spectrum utilization. In order to achieve this, we propose a multi-channel...
Error coding techniques are proposed to enhance the efficiency and reliability, and to minimize the delay of the future Internet. The need of such enhancement is established. Internally, a method is proposed for the replacement of all the Internet transmission protocol Checksums. An optimal coding algorithm is presented for all protocol applications beyond the Internet. Externally, a systematic method...
Relaying in wireless communication can improve power and quality of service. Multiple nodes share channel resources to achieve optimized power. We consider a model with fixed source, destination and relay nodes. Our model finds the optimal values for power transmission for direct and relayed transmitting nodes. In our problem we compare amplify and forward and decode and forward transmission protocols...
The advent of the mobile age has heavily changed the requirements of today's communication devices. Data transmission over interference-prone wireless channels requires additional steps of data processing, such as forward error correction, to ensure reliable communication. In this work we present RS(63,55) Reed-Solomon encoding and decoding algorithms according to the IEEE 802.15.4a standard executed...
The paper is mainly devoted to explore practical scalable video coding technologies over error-prone wireless and mobile network with fluctuant bandwidth and various terminals. The new coder supports full scalability of spatial resolution, SNR quality and temporal in a flexible and simple method. Instead of common-used but complex MCTF-based scheme the new coder integrates smartly several optimized...
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