802.16 uplink sounding via QPSK golay sequences
A construction of 802.16e-compatible uplink sounding sequences is proposed. Ideally, the sounding signals should have low Peak-to-Average Power Ratio (PAPR) and low cross correlation. Existing 802.16e sounding sequences are variations of the punctured ...
Novel asterisk 16QAM constellation for COFDM
We propose a new QAM constellation called A16QAM. This constellation leads to the better average SER and the better CFM than the existing S16QAM, while having the same OFDM PMEPR upper-bounds as S16QAM. In addition, the OFDM PMEPR built by A16QAM is ...
Reduction of power envelope fluctuations in OFDM signals by using neural networks
One of the main drawbacks of Orthogonal Frequency Division Multiplexing (OFDM) are the large fluctuations of its power envelope. In this letter, a novel and efficient scheme based on Multilayer Perceptron (MLP) Neural Networks (NN) is proposed. The NN ...
A generalization of shift-window approach for UWB lSI reduction
Mitigating inter-symbol interference (lSI) in impulse radio is one of the challenges in achieving the high data rate potential of Ultra Wideband (UWB). Available techniques such as the use of Multiband OFDM and equalizer provide a good solution but they ...
Average level crossing rate of dual selection diversity in correlated Rician fading with Rayleigh Cochannel interference
We present an infinite-series representation for the average level crossing rate (LCR) of dual selection combining (SC) receivers, operating over correlated Rician fading channels, in the presence of Rayleigh cochannel interference (CCI). Numerical ...
Amplify-and-forward relaying in channel-noise-assisted cooperative networks with relay selection
The performance of dual-hop channel-noise-assisted amplify-and-forward cooperative networks with relay selection in a clustered structure is evaluated. Exact closed-form expressions for the probability density function and cumulative distribution ...
On Maximizing VoIP capacity and energy conservation in multi-rate WLANs
This letter highlights a key problem that arises when frame aggregation, a popular method for boosting VoIP capacity, is used in Wireless Local Area Networks (WLANs) that employ asynchronous power save mode (PSM). Specifically, it shows how the PSM ...
MRMAC: medium reservation MAC protocol for reducing end-to-end delay and energy consumption in wireless sensor networks
This letter proposes a novel medium reservation MAC protocol that reduces both end-to-end delay and energy consumption for wireless sensor networks. MRMAC reduces endto-end delay by informing the intended receiver of NPAT (next packet arrival time) and ...
Minimum-outage broadcast in wireless networks with fading channels
We consider the problem of cooperative broadcasting for minimum outage in wireless networks. We consider wireless multihop broadcast as a set of transmitters that transmit in a certain order. The receiving nodes are able to combine all the previous ...
Optimal S1SO and M1MO spectral efficiency to minimize hidden-node network interference
In this letter, the optimal spectral efficiency for a given message size that minimizes the probability of causing disruptive interference for ad hoc wireless networks or cognitive radios is investigated. Implicitly, the trade being optimized is between ...
A power-saving model for roadside unit deployment in vehicular networks
In this letter, we investigate the impact on connectivity metric when a power-saving model is applied to a vehicular network. An analytic model with linear time complexity is developed to compute the optimal number of active roadside units under a ...
BER analysis of square OSTBCs with LMMSE channel estimation in arbitrarily correlated rayleigh fading channels
In this paper, we examine the bit error rate (BER) performance of square orthogonal space-time block codes (OSTBCs) under arbitrarily correlated Rayleigh fading channels. We consider a mismatched maximum-likelihood receiver that obtains the channel ...
A novel cognitive radio adaptation for wireless multicarrier systems
This paper deals with the transmission parameter adaptation problem in a dynamic wireless channel environment for multicarrier-based cognitive radio systems. Given the environmental parameters returned by sensors, the cognitive radio will select a set ...
A full transmit diversity using cyclic delay diversity for EST based modulation
This letter proposes a transmit-diversity scheme using cyclic delay diversity (CDD) and energy spreading transform (EST) based modulation. It achieves full diversity over frequency-selective fading channels as well as flat fading channels for any number ...
Morphological sampling scheme for analysis and optimization of wireless indoor environments
Algorithms used in the optimization of wireless deployments have computational time as one of their main drawbacks. This computational time is very dependent on the test points established to characterize a deployment scenario. The approach commonly ...
Symbol error performance analysis of OFDM relaying system with subcarrier mapping scheme
This letter presents a study on statistical and symbol error performance analysis of the two-hop orthogonal frequency division multiplexing (OFDM) relay link with amplify-and-forward (AF) protocol and subcarrier mapping (SCM) scheme. Closed-form ...
An improved SoS method for generating multiple uncorrelated Rayleigh fading waveforms
This paper introduces an improved method to generate multiple uncorrelated Rayleigh fading waveforms. Correlated waveforms occur occasionally when Generalized Method of Exact Doppler Spread is used. Detailed study shows how this error occurs and how to ...
Subcarrier and power allocation with multiple power constraints in OFDMA systems
This letter addresses the problem of subcarrier and power allocation over an OFDMA system with multiple power constraints. Each power constraint is related to sharing a power resource by a subset of users. Here, a framework based on time-sharing method ...
Mobile beacon-based 3D-localization with multidimensional scaling in large sensor networks
Localization is essential in wireless sensor networks to handle the reporting of events from sensor nodes. For 3- D applications, we propose a mobile beacon-based localization using classical multidimensional scaling (MBL-MDS) by taking full advantage ...
Probability of node to base station connectivity in one-dimensional ad hoc networks
In this letter, probability of node to base station connectivity in a one-dimensional ad hoc network is calculated. It is assumed that the location of the nodes follows a homogeneous Poisson point process, while the base stations are either another ...
Energy normalized correlation for signal acquisition in power-control-absent UWB networks
This letter presents a novel detection method for signal acquisition in a power-control-absent ultra-wideband (UWB) system where concurrent transmissions are unavoidable. In such a scenario, the conventional single-user detection method which is based ...
COMIC: intelligent contention window control for distributed medium access
In this letter, a scheme for Collision Mitigation with Intelligent Contention Window Control (COMIC) is proposed for backoff based collision resolution algorithm. COMIC intelligently mitigates collisions by probabilistically maximizing the selection ...
Reduced-memory decoding of low-density lattice codes
This letter describes a belief-propagation decoder for low-density lattice codes of finite dimension, in which the messages are represented as single Gaussian functions. Compared to previously-proposed decoders, memory is reduced because each message ...
A result on zetterberg codes
The family of Zetterberg codes with parameters (2u + 1, 2u + 1 - 2u) for even u is one of the best known double error correcting codes because of their large code rate and high decoding speed. In this letter, we prove that when u is odd, Zetterberg ...
Adaptive mixed scheduling for correcting errors in trapping sets of LDPC codes
Trapping sets of low-density parity-check codes are the problematic substructures that contribute to the error floor behavior under iterative decoding. Adoption of mixed scheduling for belief propagation decoding has shown to be very effective in ...
Adaptive-normalized/offset min-sum algorithm
An adaptive-normalized/offset min-sum (AN-/AOMS) algorithm for decoding low-density parity-check (LDPC) codes is proposed. Unlike the normalized/offset min-sum (NMS/OMS) algorithm, the normalization/offset factor is adaptively adjusted according to the ...
On the number of minimum stopping sets and minimum codewords of array LDPC codes
For an odd prime q and an integer m ≤ q, a binary mq × q2 quasi-cyclic parity-check matrix H(m, q) can be constructed for a class of array LDPC code C(m, q). In this letter, the closed-form formula for the numbers of minimum stopping sets of H(m, q) and ...
Connection admission control for a WDM optical network based on traffic monitoring and bandwidth release
We proposed a connection admission control (CAC) to monitor the traffic in a multi-rate WDM optical network. The CAC searches for the shortest path connecting source and destination nodes, assigns wavelengths with enough bandwidth to serve the requests, ...
Multicast handover agents for fast handover in wireless multicast networks
This Letter addresses the fast handover in wireless multicast networks. The existing multicast handover scheme tends to induce unnecessary data transmissions and large handover delay during handover. We propose a Multicast Handover Agent (MHA), which is ...
A unified notification service utilizing explicit wireless degradation notifications
The dynamic characteristics of heterogeneous networks require cross layer solutions to optimize penormance. Many cross layer solutions however, have tightly coupled Upper Layer Protocols (ULP) to lower layer performance metrics. Such an approach hinders ...
