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We present our previous work in [17] in a more generic way to construct q-ary Golay complementary sets and near-complementary sets of size N and sequence length M · Nm by using different seed sequences, where m is an arbitrary non-negative integer, M is the length of seed sequences and N is a power of 2. The boolean functions of these sequences will also be derived with our method. To illustrate it,...
This paper evaluates the performance of differentially encoded quadrature phase shift keying (DQPSK) modulated orthogonal frequency division multiplexing (OFDM) for underwater acoustic (UWA) communication. The combination of OFDM and the non-coherent detection scheme maintains the receiver design simple, reliable and spectrally efficient. QPSK helps achieve higher data rate as two bits are sent over...
LTE is well on its way to becoming the primary cellular standard, due to its performance and low cost. Over the next decade we will become dependent on LTE, which is why we must ensure it is secure and available when we need it. Unfortunately, like any wireless technology, disruption through radio jamming is possible. This paper investigates the extent to which LTE is vulnerable to intentional jamming,...
Both channel coding over a finite field and linear precoding over a complex field can improve the system performance in wireless fading channels. In this paper, we investigate the potential benefit of linear precoding in a nonbinary LDPC coded underwater acoustic OFDM system. Real precoders of small sizes are selected in different setups, in order to avoid any complexity increase at the receiver....
This paper presents a performance evaluation of OFDM LTE downlink physical layer according to the latest 3GPP specifications. Particularly, adaptive modulation and coding (AMC) is described and analyzed. This is in conjunction with the turbo decoding algorithm Max-Log-Maximum A Posteriori (Max-Log-MAP) used in soft input soft output (SISO) decoders. The performance analysis is carried out in terms...
Use of Wireless communications for Metropolitan Area Network (MAN) in consumer electronics has increased significantly in the recent past. This paper, presents the performance analysis of four different channel coding and interleaving schemes for MIMO-OFDM communications systems. A comparison is done based on the BER, hardware implementation resources requirement, and power dissipation. It also presents...
OFDM has recently been applied widely in wireless communication system due to its high data rate transmission capability with high bandwidth efficiency. Error control codes are used to protect information from errors that can occur during transmission Reed Solomon (RS) and BCH codes is one of the most important and best known classes of non binary [5]. In the present study a simulink of RS and BCH...
Due to the strong ability in combating multipath fading, OFDM has been adopted in IEEE802.11a standard and has received considerable attention. The fundamental physical layer parts of OFDM-based IEEE802.11a are modeled and simulated in this paper. Second, we discussed the bit error rate performance of BCH, cyclic and convolutional coding in AWGN channel. Moreover, the system performance of four working...
Scheduling is a fundamental component in resource (bandwidth and power) management in NG wireless networks and plays the main role in providing QoS requirements such as delay, throughput and packet loss for different classes of service in 802.16d networks. In this paper we propose a novel scheduling algorithm Strict Priority Based Adaptive modulation and Coding (SP_AMC_Based) that can grantee QoS...
The HomePlug Green PHY specification is an elegant solution to challenges that are unique to Smart Grid applications. It is a product of close collaboration between the HomePlug Alliance, the utility industry, and automobile manufacturers. The HomePlug Alliance is committed to continuing collaboration with other industries to ensure that our broadband PLC solutions continue to evolve in response to...
The Long-Term Evolution (LTE) is the next generation of current mobile telecommunication networks. LTE has a new flat radio-network architecture and a significant increase in spectrum efficiency. In this paper a link level implementation in a system-level LTE simulator is proposed. There are two important functions at link level to increase the network capacity: Link Adaptation and Dynamic Scheduling...
The emerging technology of cooperative communication has been intensively examined in the recent years. However, few investigate its combination with the Multi-band (MB) OFDM physical layer. In the paper, we propose a cooperative MB-ODFM communication with efficiently grouped relays under multipath channel. Taking advantage of the multiple bands together with the grouped relays, the proposed zero-padding...
The concerns of having a high speed data transmission over power line carriers can be resolved with many techniques including modulation and encoding schemes and synchronization techniques. The ultra wideband technology implemented in radio communication provides a better performance in a wired environment with fewer problems and as efficient as combined wireless and wired technologies for networking...
This paper proposes a novel approach of suppressing narrowband interference from a multi-subband convolutional coded orthogonal frequency division multiplexing (OFDM) system. In this system, the convolutional coded data symbols using different coding generators are transmitted in different subbands. By identifying and discarding the interfered subband(s), the interference level can be greatly reduced...
MB-OFDM UWB technology has attracted much attention in high speed wireless communications. A UWB communication system with channel coding is noticing for avoiding the performance degradation due to adverse channel propagation conditions. In this paper, we propose a novel Euclidean Geometry low-density parity-check (LDPC) coding scheme for MB-OFDM UWB systems. We emphasized on the construction of Euclidean...
We propose the use of simple full interference cancellation (FIC) and orthogonal frequency-division multiplexing (OFDM) within a two-hop asynchronous cooperative four relay network. This approach can achieve the full available diversity and asymptotically full rate. The four relay nodes are arranged as two groups of two relay nodes with offset transmission scheduling. Therefore, the source can serially...
One of the main disadvantages of OFDM (Orthogonal frequency-division multiplexing) is its high PAPR (Peak to Average Power Ratio). In this paper we propose a method for reducing PAPR using encoding and companding techniques. Several codes were used such as BCH, RS codes and Reed-Muller. The effect of modulation BPSK and QAM16 on the PAPR has been studied, μ-law companding has been used and the influence...
In Orthogonal Frequency Division Multiplexing (OFDM), multiple pilot subcarriers are dispersed for propagation channel estimation. Our study suggests a method to reduce the number of pilot subcarriers to 1/15 while maintaining fading tolerance. This can be realized by estimating the propagation channel parameters with combined implementation of sequential feedback estimation for the time direction...
Coding techniques for reducing peak-to-mean-envelope-power-ratio (PMEPR) have been intensively investigated for the orthogonal frequency division multiplexing (OFDM) systems adopting PSK, square QAM, and rectangular QAM constellations since the PMEPR is the crucial problem in OFDM. Recently, we designed a new coding method for reducing the PMEPR in OFDM built on star 16QAM constellations. In this...
We study the uplink control signaling in 3GPP-Long Term Evolution (LTE) systems. Specifically, we propose a precoding method that uses complex-field coding (CFC) to improve the performance of the PUCCH format 2 control signaling. In the case of perfect channel state information (CSI) at the receiver and with a single receive antenna, the proposed method offers significant gains compared to the coding...
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