The Infona portal uses cookies, i.e. strings of text saved by a browser on the user's device. The portal can access those files and use them to remember the user's data, such as their chosen settings (screen view, interface language, etc.), or their login data. By using the Infona portal the user accepts automatic saving and using this information for portal operation purposes. More information on the subject can be found in the Privacy Policy and Terms of Service. By closing this window the user confirms that they have read the information on cookie usage, and they accept the privacy policy and the way cookies are used by the portal. You can change the cookie settings in your browser.
In this paper, we discuss the network coverage of the generic multicarrier (or OFDM) based broadcast system by exploiting the frequency diversity over subcarriers. We first define the performance metric and discuss the relationship among broadcast rate, coverage area and the outage probability. To calculate the actual broadcast coverage area, we provide analytical results for both the low SNR and...
In this paper, we analyze the outage performance of cognitive Z-interference channel where two-path cognitive relaying is used to improve bandwidth utilization efficiency of cognitive user transmission while simultaneously leading to improvement in outage performance of primary user. Cognitive relays have non-causal message knowledge of cognitive user and use interference pre-cancellation scheme to...
Simple closed-form expressions of outage probability and moment generating function (MGF) are found for a switch and examine combiner (SEC) operating over independent and identically distributed (IID) Hoyt fading channel. Next, using the derived MGF, symbol error probability (SEP) of different M-ary modulation schemes are calculated. In addition, an analytic framework is presented for calculation...
A general channel model for multiple-input multiple-output (MIMO) free-space optical (FSO) communication systems impaired by atmospheric and misalignment fading is developed. The outage probability as a performance measure is derived and the diversity gain is analyzed. It is shown that the diversity gain is independent of the number of transmitters and receivers and only determined based on the misalignment...
Optimum combining is already mentioned to be good matched technique for suppressing the multipath fading and reducing the effect of co-channel interference (CCI) in wireless communications. It has been used for either Gaussian fading channels and non-Gaussian fading channels for different conditions and purposes. In this paper, the performance evaluation of wireless digital communication systems for...
The paper considers a wireless network in which simultaneous communications occur within multiple single antenna source-destination node pairs. An Amplify-and-Forward (AF) relay, equipped with multiple antennas, assists the communication. The relay implements linear beamforming (BF) aiming to minimize the total relay power subject to signal-to-interference ratio (SINR) constraints for each source-destination...
To improve the bandwidth efficiency of the classical orthogonal cooperative transmission scheme while maintaining the cooperative gain, a novel non-orthogonal amplify-and-forward cooperative scheme based on distributed space-time code is proposed. In this scheme, the orthogonal characteristic of Alamouti space-time code is utilized to make cooperative users relay on the shared channel resources so...
A new cooperative access protocol is presented in the context of IEEE 802.11-based fixed ad hoc networks. The protocol achieves optimal diversity-multiplexing tradeoff thanks to two known functionalities: on-demand cooperation and selection of the best relay. The on-demand approach allows maximization of the spatial multiplexing gain. The selection of the best relay allows maximization of the spatial...
Previous work on performance analyses of generalized selection combining (GSC) RAKE receivers based on the signal to noise ratio focused on the development of methodologies to derive exact closed-form expressions for various performance measures. However, some open problems related to the performance evaluation of GSC RAKE receivers still remain to be solved such that an assessment of the impact of...
In this paper, we draw our attention to the problem of interference avoidance in a macrocell-femtocell network. Further, macro user equipments operate in a Frequency Division Duplexing mode while all femtocells employ the macrocellular uplink spectrum in a Time Division Duplexing mode. We propose a self-adapting algorithm to tackle highly interfering MUEs through handover procedure. Results reveal...
In this paper, the outage performance is investigated for orthogonal frequency division multiplexing (OFDM)-based selective amplify-and-forward cooperative networks over independent but not identically distributed (i.n.i.d.) Nakagami-m fading channels, with integer values of parameter m. A unified closed-form expression for the outage probability is derived for three selective relaying schemes. The...
In this paper, we investigate the performance of the multi-input-multi-output (MIMO) relaying scheme, which combines the Alamouti code with fixed decode-and-forward (DF) protocol. Based on the relationship between the overall signal-to-noise ratio (SNR) of the system and that of the weakest hop, the closed-form expressions of outage probability and bit error probability for MPSK are derived. The analysis...
In this letter, we investigate the performance of distributed switch-and-stay network, an appropriate solution for low-complexity cooperative relaying applications, under adaptive transmission. Under Rayleigh fading channels, we are able to derive the closed-form expression of the occurrence probability, outage probability, bit error probability and achievable spectral efficiency of the system. Numerous...
In this paper, we investigate threshold-based dual-hop relaying schemes in conjunction with partial relay selection in terms of outage probability and bit error probability. The best relay chosen by partial relay selection will transmit jointly with the source using either amplify-and-forward (AF) or decode-and-forward (DF) if the received signal-to-noise ratio (SNR) exceeds a given threshold; otherwise,...
We are concerned with minimizing outage probability in a typical orthogonal frequency division multiplexing (OFDM)-based two-hop relaying network. With the instantaneous channel state information at the receiver of each relay, we drive the optimal relay selection scheme which is jointly with optimum power allocation policies, and can be implemented in a distributed way. Since the power allocation...
In this paper, exact expressions for outage and average capacity are presented for a decode-and-forward protocol with partial relay selection. An independent but not identically distributed Rayleigh fading environment is considered. Numerical and simulated results demonstrate the validity of the analytical results.
This paper presents an novel iterative generalized selection combining (IGSC) for amplify-and-forward (AF) cooperative communications based on error detection and rearranging the SNR of indirect link in decreasing order of magnitude. The destination node decides whether to accept incoming path or not in every time frame to reduce the excessive burden of maximal ratio combining (MRC) with all diversity...
Relaying technique has been developed considerable attention in response to improve reliability and to extend wireless network coverage. One of conventional relaying technique, incremental relaying which uses limited feedback from the destination has attracted research attention because of performance and minimization of relay usage. Moreover, optimal power allocation for various relaying schemes...
This paper presents the outage analysis of multiple-input multiple-output (MIMO) block-fading channels with nearest neighbour decoding and mismatched channel state information at the receiver (CSIR). Based on mismatched decoding arguments, we demonstrate the achievability of the generalised outage probability, the probability that the generalised mutual information (GMI) is less than the target data...
We present an analytical performance study of selection diversity (SD) with multiple amplify-and-forward relays in independent and identically distributed (i.i.d.) Nakagami-m fading channels. Employing SD is an attractive approach to achieve bandwidth and power efficiencies, by utilizing only a single diversity path with the strongest end-to-end signal-to-noise ratio (SNR) to transmit. For such systems,...
Set the date range to filter the displayed results. You can set a starting date, ending date or both. You can enter the dates manually or choose them from the calendar.