Online ISSN
1751-8636
Print ISSN
1751-8628
IET Communications
Volume 5, Issue 16, 4 November 2011
Volumes & issues:
Volume 5, Issue 16
4 November 2011
-
- Author(s): Y.F. Wei ; F. Richard Yu ; M. Song ; Y. Zhang
- Source: IET Communications, Volume 5, Issue 16, p. 2257 –2265
- DOI: 10.1049/iet-com.2010.0759
- Type: Article
- + Show details - Hide details
-
p.
2257
–2265
(9)
Cooperative relaying technology is considered as a promising solution for the high data-rate coverage required in future wireless communication systems, where provision of reliable multimedia or data services for transmission control protocol (TCP) applications is of extreme importance. However, while the performance of cooperative relaying protocols has been extensively studied over physical layer, little attention has been paid to the impact of selection relaying on TCP performance. The authors investigate the TCP throughput in cooperative relaying networks and take a cross-layer design approach when selecting a relay to optimise the TCP throughput. The authors use first-order finite-state Markov channel to model the wireless time-varying channels, and formulate the cross-layer TCP throughput optimisation problem as a restless bandit system, which is a powerful stochastic control modelling framework and can be solved using linear programming algorithm. Simulation results were presented to illustrate the effectiveness of the proposed scheme. It was shown that the TCP throughput is determined by physical layer channel state and link-layer frame size and retransmission time. - Author(s): M. Naeem ; U. Pareek ; D.C. Lee
- Source: IET Communications, Volume 5, Issue 16, p. 2266 –2274
- DOI: 10.1049/iet-com.2011.0043
- Type: Article
- + Show details - Hide details
-
p.
2266
–2274
(9)
The authors investigate the interference-aware joint secondary user (SU) selection/scheduling and quantised power control (JSUS-QPC) schemes for the uplink communication in the cognitive multiple-input multiple-output (MIMO) system. The main objective of JSUS-QPC is to maximise the sum-rate capacity of the cognitive MIMO uplink communication system under the constraint that the interference to the primary user (PU) is below a specified level. The computational complexity of finding an optimal JSUS-QPC scheme by exhaustive search grows exponentially with the number of users and power levels. The authors also show that the JSUS-QPC is a non-deterministic polynomial-time hard problem and present two low-complexity algorithms for JSUS-QPC problem. Also, the effect of different system parameters (e.g. interference threshold level, the number of PUs, the number of SUs, the number of quantised power levels, etc.) on the performance of the proposed algorithms is examined. The proposed algorithms have low computational complexity, and their effectiveness is verified through simulation results. - Author(s): R. Barazideh and B. Seyfe
- Source: IET Communications, Volume 5, Issue 16, p. 2275 –2284
- DOI: 10.1049/iet-com.2010.0386
- Type: Article
- + Show details - Hide details
-
p.
2275
–2284
(10)
In this study the authors provide an adaptive cross-layer design that maximises the spectral efficiency under prescribed quality of services (QoSs) such as error rate and delay. The considered scheme combines adaptive modulation at physical layer with a truncated automatic repeat request at data link layer in the presence of both channel estimation and prediction errors. Both the channel estimation and prediction are done based on adaptive pilot-symbol-assisted modulation in which both pilot spacing and power allocation on pilot symbols are optimised in order to maximise the spectral efficiency. We provide closed-form expression for average spectral efficiency and average packet error rate over Rayleigh fading channel. Numerical results demonstrate that our adaptive cross-layer design improves the spectral efficiency while meeting the prescribed QoS. We have shown that the channel prediction is more important than the channel estimation in order to improve the spectral efficiency in a practical situation. Also we have found that the increment of spectral efficiency decreases on increasing the maximum number of retransmissions, and thus in order to reduce the delay and buffer size at the data link layer, the maximum number of retransmissions are limited to a small number in practice. - Author(s): R. Feick ; L. Ahumada ; H. Carrasco
- Source: IET Communications, Volume 5, Issue 16, p. 2285 –2290
- DOI: 10.1049/iet-com.2011.0037
- Type: Article
- + Show details - Hide details
-
p.
2285
–2290
(6)
This study presents an empirical characterisation of the wireless channel observed by static users in settings that correspond to populated open public spaces, where wireless services are increasingly being deployed. Link stability is analysed in terms of the temporal K-factor of the Ricean distribution. Second-order statistics were parameterised in terms of the Doppler shift, coherence time and level crossing rates. The authors found that the volume of pedestrian traffic had a very significant effect on the temporal K-factor, overshadowing the influence of line-of-sight or lack of it in the link. On the other hand, the volume of pedestrian traffic in the environment had no detectable effect on the second-order statistics of the channel. - Author(s): Q. Han ; Y. Bai ; L. Gong ; W. Wu
- Source: IET Communications, Volume 5, Issue 16, p. 2291 –2300
- DOI: 10.1049/iet-com.2010.0946
- Type: Article
- + Show details - Hide details
-
p.
2291
–2300
(10)
Mobile ad hoc networks (MANETs) are becoming increasingly important. The most challenging issue in conjunction with MANETs is reliable routing, that is, the procedure that determines the trajectory of packets travelling over the network. The authors present a novel link availability-based routing protocol (LBRP) for MANETs. Compared with other routing protocols, LBRP takes unpredictable topology change and frequent link failure into account. Meanwhile, by a rough estimation of the distance between two adjacent nodes, the proposed approach is able to accurately predict link availability over a short period of time. Simulation results are given to verify the approach. This study could serve as groundwork for further MANET research, including analysing and optimising other network protocols. Reliable routing protocol can effectively improve the availability and reliability of upper layer services and quality of service. - Author(s): W.-H. Fang ; M.-J. Deng ; Y.-T. Chen
- Source: IET Communications, Volume 5, Issue 16, p. 2301 –2309
- DOI: 10.1049/iet-com.2010.1083
- Type: Article
- + Show details - Hide details
-
p.
2301
–2309
(9)
This study presents some joint source and relay power allocation algorithms in the amplify-and-forward (AF) relay networks using the efficacious geometric programming (GP). According to the constraints, approximate expressions of the received signal-to-noise ratio are first obtained. Thereafter, the problems are cast into appropriate GP forms according to the constraints. The power allocated to the source(s) and to the relays is then determined iteratively via the single condensation method. The new GP approach is shown to be applicable to a variety of constraints by using all of the relays for assistance and is amenable to asymmetric channels in both the single-user and multi-user AF relay networks. Conducted simulations show that the proposed power allocation schemes can attain superior performance compared with the previous works under various constraints in miscellaneous scenarios. - Author(s): Y.-P. Shieh and W.-H. Hsu
- Source: IET Communications, Volume 5, Issue 16, p. 2310 –2316
- DOI: 10.1049/iet-com.2011.0050
- Type: Article
- + Show details - Hide details
-
p.
2310
–2316
(7)
The border gateway protocol (BGP) handles the task of establishing paths between autonomous systems (AS). As the BGP does not incorporate measures of round-trip time into the decision and does not provide path diversity for a destination, this study proposes a simple path diversity algorithm (SPDA) for interdomain routing. The SPDA comprises three steps. First, the BGP is extended to allow the BGP routing table to save multiple paths for any destination. Second, a given source node determines whether the point of congestion occurs along the best path. Third, if congestion occurs along the best path, the source node specifies an alternate path and directs traffic over the best and alternate paths concurrently. Simulation results indicate that the SPDA produces better performance than existing approaches in average end-to-end delay, average packet loss rate and average throughput. - Author(s): K.J. Kulikowski and M.G. Karpovsky
- Source: IET Communications, Volume 5, Issue 16, p. 2317 –2327
- DOI: 10.1049/iet-com.2011.0096
- Type: Article
- + Show details - Hide details
-
p.
2317
–2327
(11)
For many devices and circuits, even a single fault can result in errors of a large Hamming weight at the output of a device, complicating the task of error detection and correction. Traditional error detection and correction techniques are based on linear error-detecting codes that are designed to detect or correct errors of a small multiplicity or burst errors. The authors present codes and architectures suitable for both online and offline error detection and correction which can detect and correct any error of any multiplicity by exploiting the laziness of error manifestation. Faults in many combinational circuits can lead to ‘lazy’ or repeating errors at the outputs of a device to be protected. The proposed decoding algorithms can correct any error of any Hamming weight if the same error affects at least three different consecutive distorted output vectors of a protected device for binary algebraic errors. Likewise, the proposed decoding algorithms can correct any error of any Hamming weight if the same error affects two different output vectors of a protected device for arithmetic errors. - Author(s): M. Shaat and F. Bader
- Source: IET Communications, Volume 5, Issue 16, p. 2328 –2338
- DOI: 10.1049/iet-com.2010.1062
- Type: Article
- + Show details - Hide details
-
p.
2328
–2338
(11)
An efficient fairness-aware uplink resource allocation algorithm in orthogonal frequency-division multiplexing-based cognitive radio systems is presented. The proposed resource allocation algorithm is divided into two steps. The subcarriers to user assignment is first performed, and then the power is allocated to the different subcarriers. The objective is to maximise the total data rate while guaranteeing that the interference introduced to the primary system is under the prescribed interference temperature limit. The fairness among users is considered within the subcarrier allocation by reducing the probability of having users whose instantaneous rates are below a given minimum rate. Many factors will be considered during the resource allocation process like the channel quality, potential interference caused to the primary bands, instantaneous rate achieved by every user and the increment in the total data rate. Simulation results confirm the efficiency of the proposed algorithm. - Author(s): M. Seyfi ; S. Muhaidat ; J. Liang
- Source: IET Communications, Volume 5, Issue 16, p. 2339 –2344
- DOI: 10.1049/iet-com.2010.1033
- Type: Article
- + Show details - Hide details
-
p.
2339
–2344
(6)
The authors investigate the effect of feedback delay on the average capacity of a decode-and-forward cooperative network with relay selection. In particular, a multi-relay cooperative scenario is considered, where the best relay is selected from a subset of relays that are able to decode the source information correctly. In this selection scenario, the authors assume that the destination terminal estimates the relay-to-destination (R→D) channel-state-information perfectly and sends the index of the best relay to the relay terminals via a delayed feedback link. The authors investigate the performance of the considered scenario in terms of average capacity. Simulation results are presented to corroborate the analytical results. - Author(s): P.D. Arjona-Villicaña ; C.C. Constantinou ; A.S. Stepanenko
- Source: IET Communications, Volume 5, Issue 16, p. 2345 –2355
- DOI: 10.1049/iet-com.2010.0905
- Type: Article
- + Show details - Hide details
-
p.
2345
–2355
(11)
A new framework to perform routing at the autonomous system (AS) level is proposed here. This mechanism, called chain routing framework (CRF), uses complete orders as its main topological unit. Since complete orders are acyclic digraphs that possess a known topology, it is possible to use these acyclic structures to route consistently packets between a group of ASs. The adoption of complete orders also allows easy identification and avoidance of persistent route oscillations, eliminates the possibility of developing transient loops in paths and provides a structure that facilitates the implementation of traffic engineering. Moreover, by combining CRF with other mechanisms that implement complete orders in time, the authors propose that it is possible to design a new routing protocol, which can be more reliable and stable than the border gateway protocol. - Author(s): S. Leu and R.-S. Chang
- Source: IET Communications, Volume 5, Issue 16, p. 2356 –2363
- DOI: 10.1049/iet-com.2010.0341
- Type: Article
- + Show details - Hide details
-
p.
2356
–2363
(8)
In recent years, mobile ad hoc network (MANET) has gained a lot of attention because of its self-organising and infrastructure-free characteristics. Unlike the traditional wireless networks, each node in MANET can act as a router to receive and forward packets. All nodes can randomly move around, leave the network or switch off. Hence, broadcasting has been widely used in diffusing data, routing or topology information in MANET. Unfortunately, MANET may be filled with a large number of redundant broadcasting packets. Furthermore, in order to transmit the broadcasting packets, each mobile node (MN) competes for the limited radio channels. Thus, packet collision is serious. All of these aforementioned conditions are called the ‘Broadcast Storm Problem’. Not only does it occupy the network bandwidth but it also consumes the battery of MNs. In this study, the authors propose an algorithm that is different from previous works to solve the Broadcast Storm Problem. The algorithm is suitable for a dynamic MANET environment. - Author(s): P.G. Farrell ; L.J. Arnone ; J. Castiñeira Moreira
- Source: IET Communications, Volume 5, Issue 16, p. 2364 –2370
- DOI: 10.1049/iet-com.2010.1040
- Type: Article
- + Show details - Hide details
-
p.
2364
–2370
(7)
A new antilog–sum algorithm for decoding error-correcting codes is described. The soft-input, soft-output (SISO) algorithm uses squared Euclidean distance as the metric, does not require knowledge of the signal-to-noise ratio of the received signal and is less complex to implement than other SISO algorithms. The results of simulations show that the performance is very close to that of the log–sum–product algorithm. - Author(s): G. Abbas ; A.K. Nagar ; H. Tawfik
- Source: IET Communications, Volume 5, Issue 16, p. 2371 –2385
- DOI: 10.1049/iet-com.2010.0163
- Type: Article
- + Show details - Hide details
-
p.
2371
–2385
(15)
This study concerns the problem of controlling multiclass (elastic, inelastic and unresponsive) Internet traffic without sacrificing quality of service (QoS) by adopting a unified ‘resource allocation and traffic management’ approach. The aim is to minimise the need for relying on dedicated QoS traffic control mechanisms in order to avoid spiralling complicatedness that, in practice, leads to ‘robust yet fragile’ Internet. In order to address this challenge, the authors first introduce an end-to-end non-convex network utility maximisation-based resource allocation algorithm to guarantee enhanced QoS to elastic and inelastic flows. Then, a pricing-based fair and scalable traffic management scheme, called Purge, is introduced to protect transmission control protocol-friendly traffic from unfairness attacks by unresponsive flows. Finally, the main contribution of this work, the unified algorithm, is developed by adapting Purge to complement link-control of the proposed resource allocation algorithm to enable it to enforce fairness while maintaining a scalable network core. The unified approach thus delivers QoS guarantees for multiclass traffic. - Author(s): H.X. Nguyen ; H.H. Nguyen ; T. Le-Ngoc
- Source: IET Communications, Volume 5, Issue 16, p. 2386 –2396
- DOI: 10.1049/iet-com.2010.0830
- Type: Article
- + Show details - Hide details
-
p.
2386
–2396
(11)
An incremental relaying protocol based on the adaptive decode-and-forward relaying scheme is presented for a cooperative wireless network with binary frequency-shift keying modulation. To reduce error propagation and satisfy bit-error-rate (BER) requirement, the proposed protocol employs two thresholds. One threshold is used to select reliable relays: if a relay is requested to re-trnsmit, it will do so if its decision variable is larger than the threshold; otherwise, it remains silent. The other threshold is used at the destination as follows: the destination sends a request to re-transmit if the decision variable corresponding to a received signal is smaller than the threshold, otherwise, the destination sends a request to stop re-transmissions. The destination combines the signals from the requested relays and from the source to make the final decision. Very-tight closed-form upper bounds for both the average BER and throughput are derived for the proposed protocol. Based on the obtained BER and throughput expressions, the problem of choosing optimal thresholds to maximise the throughput while the BER meets a given constraint is investigated. Simulation results show that our proposed protocol leads to a considerable improvement in the performence of cooperative diversity systems. - Author(s): X. Feng and H.-C. Wu
- Source: IET Communications, Volume 5, Issue 16, p. 2397 –2406
- DOI: 10.1049/iet-com.2010.0742
- Type: Article
- + Show details - Hide details
-
p.
2397
–2406
(10)
The transmitter identification (TxID) of digital television (DTV) systems becomes crucial nowadays. TxID (or transmitter fingerprinting) technique is used to detect, diagnose and classify the operating status of any radio transmitter of interest. The TxID system is specified in Advanced Television System Committee (ATSC) A/110 standard where pseudorandom sequences are proposed to be embedded into the DTV signals before transmission. The buried ratio or injection level of injected Kasami sequences in DTV-TxID systems will both affect the identification correctness and the DTV reception quality. In this study, the authors investigate the important unsolved optimisation problem for injection level. The authors present the new analysis here for the realistic scenario consisting of multiple transmitters and receivers over the additive white Gaussian noise channel. The signal-to-interference-plus-noise ratios for the TxID signal detection and the subject TV signal reception are both considered as two essential measures for single-frequency networks. Besides, the authors design a novel efficient injection-level optimisation scheme for TxID simply based on the given information including the signal-to-noise ratio at the receiver and the locations of the transmitters and the receiver(s). - Author(s): P. Sedtheetorn ; K. Hamdi ; L. Wuttisittikuljit
- Source: IET Communications, Volume 5, Issue 16, p. 2407 –2417
- DOI: 10.1049/iet-com.2010.0535
- Type: Article
- + Show details - Hide details
-
p.
2407
–2417
(11)
This study presents a system-level theoretical analysis of two different types of multirate code division multiaccess (CDMA) wireless communication systems, which include both variable spreading gain (VSG) CDMA and multicode (MCD) CDMA systems. Based on the accurate interference models, the authors derive unified expressions of the cumulative density function of the signal-to-interference-plus-noise ratio in the cases of both binary and quaternary multirate CDMA schemes. This leads us to achieve new packet error rate expressions, which consider the impacts of bit-to-bit error dependence, optimal power transmissions and random users’ distributions, for multirate-slotted packet CDMA systems. The expressions are used to investigate the system-level performance of VSG and MCD-based multicellular CDMA networks over Rayleigh fading environment. - Author(s): L. Zhao ; L. Jin ; W.F. Liu ; K.Z. Huang ; W.Y. Luo
- Source: IET Communications, Volume 5, Issue 16, p. 2418 –2429
- DOI: 10.1049/iet-com.2010.0761
- Type: Article
- + Show details - Hide details
-
p.
2418
–2429
(12)
At present, the fixed spectrum allocation is the accepted strategy employed by the wireless industry and regulators and a large number of spectrum resources have been wasted because of the traffic load variation in different heterogeneous wireless networks. Through the analysis of recent research about dynamic spectrum allocation (DSA), vertical handoff and multi-mode base stations, the authors have proposed the shared carrier vertical network transformation (SCVNT) algorithm, which is based on minimum total blocking probability (MTBP) or minimum redundant channel difference (MRCD). In order to evaluate the performance of SCVNT, the cellular system model and user mobility model are established, and using fixed channel allocation and dynamic channel allocation in each network, the theoretical analysis and simulation experiments are made in different user mobility conditions, different SCVNT judgment periods and different thresholds of the redundant channel difference. The results indicate that SCVNT can effectively reduce total blocking probability and enhance fairness in heterogeneous wireless networks with good compatibility and applicability.
Transmission control protocol throughput optimisation in cooperative relaying networks through relay selection
Interference-aware joint user selection and quantised power control schemes for uplink cognitive multiple-input multiple-output system
Cross-layer combining of adaptive pilot-symbol-assisted modulation with truncated automatic repeat request in the presence of imperfect channel state information at both the receiver and the transmitter
Effect of pedestrian traffic on fade statistics of fixed wireless links in public spaces
Link availability prediction-based reliable routing for mobile ad hoc networks
Joint source and relay power allocation in amplify-and-forward relay networks: a unified geometric programming framework
Simple path diversity algorithm for interdomain routing
Robust correction of repeating errors by non-linear codes
Efficient resource allocation algorithm for uplink in multicarrier-based cognitive radio networks with fairness consideration
Average capacity performance of opportunistic relay selection with outdated CSI
Chain routing: a new routing framework for the Internet based on complete orders
Simple algorithm for solving broadcast storm in mobile ad hoc network
Euclidean distance soft-input soft-output decoding algorithm for low-density parity-check codes
On unified quality of service resource allocation scheme with fair and scalable traffic management for multiclass Internet services
Throughput maximisation in non-coherent cooperative networks
Injection-level optimisation for digital television transmitter identification systems using Kasami sequences
Accurate packet error rate analysis of variable spreading gain-code division multiaccess and multicode-code division multiaccess wireless communication networks
Shared carrier vertical network transformation algorithm for constant bit rate service
Most viewed content for this Journal
Article
content/journals/iet-com
Journal
5
Most cited content for this Journal
-
A review on security threats, vulnerabilities, and counter measures of 5G enabled Internet‐of‐Medical‐Things
- Author(s): Mohammad Kamrul Hasan ; Taher M. Ghazal ; Rashid A. Saeed ; Bishwajeet Pandey ; Hardik Gohel ; Ala’ A. Eshmawi ; S. Abdel‐Khalek ; Hula Mahmoud Alkhassawneh
- Type: Article
-
Compressive sensing-based coprime array direction-of-arrival estimation
- Author(s): Chengwei Zhou ; Yujie Gu ; Yimin D. Zhang ; Zhiguo Shi ; Tao Jin ; Xidong Wu
- Type: Article
-
Massive MIMO: survey and future research topics
- Author(s): Daniel C. Araújo ; Taras Maksymyuk ; André L.F. de Almeida ; Tarcisio Maciel ; João C.M. Mota ; Minho Jo
- Type: Article
-
Performance analysis of non-orthogonal multiple access in downlink cooperative network
- Author(s): Jinjin Men and Jianhua Ge
- Type: Article
-
Non-orthogonal multiple access schemes with partial relay selection
- Author(s): Sunyoung Lee ; Daniel Benevides da Costa ; Quoc-Tuan Vien ; Trung Q. Duong ; Rafael Timóteo de Sousa Jr.
- Type: Article
