WLAN Technologies for Audio Delivery by Nicolas-Alexander Tatlas, Andreas Floros, Thomas Zarouchas, John Mourjopoulos

“…A detailed study of the IEEE802.11e protocol (currently under ratification) is also presented and all relevant distortions are assessed via an analytical and experimental methodology. …”
Get full text

Metamaterial Embedded Wearable Rectangular Microstrip Patch Antenna by J. G. Joshi, Shyam S. Pattnaik, S. Devi

“…This paper presents an indigenous low-cost metamaterial embedded wearable rectangular microstrip patch antenna using polyester substrate for IEEE 802.11a WLAN applications. The proposed antenna resonates at 5.10 GHz with a bandwidth and gain of 97 MHz and 4.92 dBi, respectively. …”
Get full text

Reconstruction of LDPC code sparse check matrix based on modified LBP decoding by ZHANG Tianqi, LI Chunyun, WU Xianyue, WU Yunge

“…The simulation results show that the reconstruction rate of sparse check matrix of (648,324) LDPC codes in IEEE 802.11n protocol is improved by 52.16% compared with the existing algorithms, and can reach 92.28% at high BER of 0.004 5.…”
Get full text

Design of a CPW-Fed Band-Notched UWB Antenna Using a Feeder-Embedded Slotline Resonator by Amin M. Abbosh

“…The results also reveal that the use of the resonator in the feeder of the antenna efficiently rejects any undesired subband, such as the 4.9–5.9 GHz band assigned for IEEE802.11a and HIPERLAN/2. The gain of the antennas with the resonator is about 2.2 dBi at the passband, while it is less than −8 dBi at the rejected subband.…”
Get full text

Research on scheduled WLAN MAC protocol with failure retries on RoF-DAS architecture by Zheng GUAN, Lei XIONG, Yao JIA, Min HE, Zhijun YANG

“…Aim to reduce control frames consumption and improve the delay performance,a scheduled gated-service polling access (SGPA) mechanism was proposed,in which the total data packets in the buffer at the polling instant were aggregated into a data set,that was transmitted and acknowledged uniformly.Then,an inner-arrival gated-service polling (IAGP) model was proposed to analyze the quantitative relationship between failure retry mechanism and network access performance of the wireless local area network (WLAN) in RoF-DAS.The failure retry mechanism were modeled as the arrival and service process of inner customers in IAGP.Using the Markov chain and generating function method,the closed-form expressions for the quantitative relationship between delay performance and retrial parameters,such as retry times,and the probability of retransmission,were achieved.The simulation results show that the proposed SGPA can achieve a lower delay than IEEE 802.11,and the theoretical performance evaluation calculated by IAGP are identical with the simulation results,which provides an effective evaluation mechanism for the access performance in RoF-DAS WLAN,with inperfect channel and failure retry mechanism.…”
Get full text

Compact Dual-Band Dipole Antenna with Asymmetric Arms for WLAN Applications by Chung-Hsiu Chiu, Chun-Cheng Lin, Chih-Yu Huang, Tsai-Ku Lin

“…This feature enables it to cover the required bandwidths for wireless local area network (WLAN) operation at the 2.4 GHz band and 5.2/5.8 GHz bands for IEEE 802.11 a/b/g standards. More importantly, the compact size (7 mm × 24 mm) and good radiating performance of the antenna are profitable to be integrated with wireless communication devices on restricted RF-elements spaces.…”
Get full text

Reconstruction of sparse check matrix for LDPC at high bit error rate by Zhaojun WU, Limin ZHANG, Zhaogen ZHONG, Renxin LIU

“…In order to reconstruct the sparse check matrix of LDPC, a new algorithm which could directly reconstruct the LDPC was proposed.Firstly, according to the principle of the traditional reconstruction algorithm, the defects of the traditional algorithm and the reasons for the defects were analyzed in detail.Secondly, based on the characteristics of sparse matrix, some bit sequences in code words were randomly extracted for Gaussian elimination.At the same time, in order to reliably realize that the extracted bits sequence could contain parity check nodes, the multiple random variables were determined based on the probability of containing check nodes in one extraction.Finally, the statistical characteristics of LDPC under the suspected check vector was analyzed.Based on the minimum error decision rule, the sparse check vector was determined.The simulation results show that the rate of reconstruction of most LDPC in IEEE 802.11 protocol can reach more than 95% at BER of 0.001, and the noise robustness of the proposed method is better than that of the traditional algorithm.At the same time, the new algorithm not only does not need sparseness of parity check matrix, but also has the good performance for both diagonal and non-diagonal check matrix.…”
Get full text

Reliable and Swift Message Broadcast Method in Vehicular Ad Hoc Networks by Jaesung Park, Yujin Lim

“…However, the broadcast method specified in the IEEE 802.11p does not have a collision avoidance procedure and receivers do not acknowledge when they receive a broadcast frame. …”
Get full text

Study on a cooperative MAC protocol with priority-based contention for wireless networks by LIU Yun, LIU Kai, ZENG Feng

“…A cooperative medium access control protocol with priority-based contention（PBC-CMAC） was presented for wireless networks.In the protocol,a source node preselected two optimal relays from its local relay information table,and set their priorities in cooperative request-to-send（CRTS） packet based on the relay efficiency,which reflects the de-gree of its saved transmission time.Through overhearing the handshakes between the source node and destination node,the two candidate relays can obtain instantaneous transmission rate among source node,destination node and themselves,and then contend to be the final relay without contention collisions according to their priorities and rate information.The proposed protocol can rapidly select the optimal relay to cooperatively transmit data packets under current channel qual-ity without contention collisions from all the potential relays,increase the successful probability of relay selection and cooperation efficiency,and then improve multiple access performance.Simulation results show that the proposed proto-col outperforms IEEE 802.11 request-to-send/clear-to-send（RTS/CTS） and CoopMAC protocols.…”
Get full text

Impact of Background Traffic on Speech Quality in VoWLAN by Peter Počta, Peter Kortiš, Martin Vaculík

“…This paper describes measurements of the impact of background traffic on speech quality in an environment of WLANs (IEEE 802.11). The simulated background traffic consists of three types of current traffics in telecommunication networks such as data transfer service, multimedia streaming service, and Web service. …”
Get full text

A broadcast scheme for vehicle-to-pedestrian safety message dissemination by Odongo Steven Eyobu, Jhihoon Joo, Dong Seog Han

“…This approach reduces the pedestrian device energy consumption and end-to-end delay and improves the packet delivery ratio compared to the vehicular broadcast approach for safety messages defined in the IEEE 802.11 standard.…”
Get full text

A Throughput Analysis Using a Non-Saturated Markov Chain Model for LTE-LAA and WLAN Coexistence by Mun-Suk Kim

“…The LTE-LAA system ensures efficient coexistence with other existing unlicensed systems by incorporating listen-before-talk functionality and conducting random backoff operations similar to those in the IEEE 802.11 distributed coordination function. In this paper, we propose an analytical model to calculate the throughput of each system in a scenario where a single LTE-LAA system shares an unlicensed channel with multiple wireless local area network (WLAN) systems. …”
Get full text

A new miniaturized multi-band transparent antenna for V2X communication by Ourahou Omar, Belahrach Hassan, Ghammaz Abdelilah

“…The suggested design is designed to cover vehicular communication standards such as DSRC/IEEE 802.11p at 5.9 GHz and cellular V2X (C-V2X) bands. …”
Get full text

A UWB Band-Pass Antenna with Triple-Notched Band Using Common Direction Rectangular Complementary Split-Ring Resonators by Bo Yan, Di Jiang, Ruimin Xu, Yuehang Xu

“…The proposed antenna can block interfering signals from C-band satellite communication systems, IEEE802.11a, and HIPERLAN/2 WLAN systems for example. …”
Get full text

Reconstruction of LDPC code check matrix based on random extraction at high bit error rate by Zhongyong WANG, Zhenghao LI, Kexian GONG, Peng SUN, Qingtao LI

“…In order to improve the performance of the sparse check matrix reconstruction algorithm of LDPC codes at high BER, an open set recognition algorithm of the check matrix with strong fault tolerance under the condition of sufficient and insufficient number of received code words was proposed.Firstly, a new code word space was constructed by randomly extracting part bits of the code words for many times.Gaussian elimination method was used to solve the dual vector and restore the check vector in a lower dimension.Secondly, using the check vector, the proportion of error-free code groups in the received data was continuously increased by using the methods of “eliminating error code words” or“flipping the lowest unreliable bits” for iterative processing.Simulation results show that the proposed algorithm is superior to comparison algorithm under different bit error rates, different code lengths, different code rates and different number of code words.For (648,324) LDPC codes in IEEE 802.11n protocol, when the number of received code words is sufficient, the reconstruction rate of check matrix can reach more than 95% under the condition of bit error rate of 0.003.When the number of received code words is insufficient (the number of code words is 450), the reconstruction rate of check matrix can reach more than 90% under the condition of bit error rate of 0.0015.…”
Get full text

Research on FTTR WLAN indoor wireless location algorithm based on frequency response by Zhifeng LONG, Jing ZHANG

“…Highly accurate and reliable indoor wireless positioning services have been widely used.In order to obtain good positioning accuracy, the design of positioning algorithms needs to be matched with wireless positioning facilities.fiber to the room (FTTR) is an indoor access network solution based on IEEE 802.11 ax, a new generation of wireless local area network (WLAN) standard.Compared with the existing Wi-Fi networks, FTTR has a much larger available band width.However, FTTR WLAN also lacks of a public valid data set to support localization functions, which makes the localization research based on FTTR scenarios face huge obstacles.In order to solve the above problems, firstly, a frequency response-based FTTR scene dataset generation method was proposed, which uses the existing Wi-Fi localization dataset to generate the frequency response matrix within the available band width of FTTR.Then, the parallel path principal component analysis (PCA) method was used to generate the classification matrix.And the generated dataset was trained using a fully connected neural network to improve the accuracy.The experimental results on the real measurement dataset show that the proposed localization algorithm can achieve a localization accuracy of less than 1 m, which is not only more accurate than the traditional location estimation algorithm, but also basically meets the fine-grained localization requirements for practical applications.…”
Get full text

A review of wireless access vehicular environment multichannel operational medium access control protocols: Quality-of-service analysis and other related issues by Illa Ul Rasool, Yousaf Bin Zikria, Sung Won Kim

“…Wireless access vehicular environment comprises the IEEE 802.11p and IEEE 1609.4 standards responsible for handling medium access control and transmission mechanisms in vehicular ad hoc networks. …”
Get full text

A Differential Probability Selection MAC Protocol Considering Energy Consumption in Wireless Sensor Networks by Myungsub Lee, Chang-Hyeon Park

“…The simulation using ns-2, a widely used network simulation package, gives that the proposed method can reduce the latency considerably as compared to the conventional IEEE 802.11 MAC protocols for a sensor network with up to 256 nodes. …”
Get full text

Congestion-Adaptive and Delay-Sensitive Multirate Routing Protocol in MANETs: A Cross-Layer Approach by Mahadev A. Gawas, Lucy J. Gudino, K. R Anupama

“…Since the wireless channel is shared among the neighbors in MANETs, determining delay-sensitive and congestion-aware routes using the IEEE 802.11 MAC is still a challenging problem. This paper proposes a novel cross-layer approach called congestion-adaptive and delay-sensitive multirate (CADM) routing protocol in MANETs. …”
Get full text

Synchronous Remote Rendering for VR by Viktor Kelkkanen, Markus Fiedler, David Lindero

“…., with latency equal to locally rendered VR, 0.009% stalls were observed while using a wired Ethernet connection and 0.058% stalls when using 5 GHz wireless IEEE 802.11 ac.…”
Get full text