| Title | Anti-Jamming Performance Analysis of CSS-Based Communication Systems |
| Author | *Young-po Lee (School of Information and Communication Engineering, Sungkyunkwan University, Republic of Korea), Seungsoo Yoo, Sun Yong Kim (Department of Electronics Engineering, Konkuk University, Republic of Korea), Seokho Yoon (School of Information and Communication Engineering, Sungkyunkwan University, Republic of Korea) |
| Page | pp. 101 - 104 |
| Keyword | chirp, CSS, jamming, anti-jamming, AJ |
| Abstract | Due to its anti-jamming capability, chirp spread spectrum (CSS) technique has attracted much attention in the area of wireless communications. However, there has been little rigorous analysis for the anti-jamming performance of CSS-based communication systems. In this paper, we present analytic results on the anti-jamming performance of a CSS-based system: BER expressions are derived for a CSS-based differential quadrature phase shift keying (DQPSK) system in the presence of broadband jamming signals over additive white Gaussian noise (AWGN) and Rayleigh fading channels, respectively. The numerical results show that the empirical BER closely agrees with the analytic results and CSS-based DQPSK systems can provide a significant improvement in performance over the conventional DQPSK systems that do not incorporate the CSS. |
| Title | A Closed Form BER Expression for an Overlap-Based CSS System |
| Author | *Taeung Yoon (Sungkyunkwan University, Republic of Korea), Seung Hwan Yoo, Sun Yong Kim (Konkuk University, Republic of Korea), Seokho Yoon (Sungkyunkwan University, Republic of Korea) |
| Page | pp. 105 - 108 |
| Keyword | chirp, overlap, CSS, DM |
| Abstract | Overlap is one of the techniques for increasing bit rate in CSS. More overlaps can offer higher data throughput; however, they may cause more intersymbol interference (ISI) at the same time, resulting in serious bit error rate (BER) performance degradation. This implies that the number of overlaps should be decided according to the required system performance. In this paper, we derive a closed form expression for BER of the overlap-based CSS system, which would be very helpful in setting the number of overlaps. The numerical results demonstrate that the BER derived in a closed form closely agrees with the simulated BER. |
| Title | Design of Framed and Slotted Time Structure for ALOHA-based Collision Arbitration Scheme in RFID Networks |
| Author | *Jin Kyung Park, Woo Cheol Shin, Jun Ha (Dankook University, Republic of Korea), Chulhun Seo (Soongsil University, Republic of Korea), Joonmo Kim, Cheon Won Choi (Dankook University, Republic of Korea) |
| Page | pp. 109 - 112 |
| Keyword | RFID, framed slotted ALOHA, cognizance ratio, optimal time structure |
| Abstract | Consider an RFID network which consists of a reader and a crowd of tags sojourning in the vicinity of the reader. In the RFID network, a response of a tag may collide with responses of other tags. However, the time for the reader's cognizing the tag is limited in the network. Assuming a framed and slotted ALOHA for arbitrating a collision, we choose the cognizance ratio for given cognizance time as a key performance measure. Then, we formulate a problem to find an optimal structure of framed and slotted time which maximizes the cognizance ratio under a costraint on the cognizance time. In some simple cases, we present an optimal time structure analytically. Also, we confirm that there exists a non-trivial number of frames which maximizes the cognizance ratio for given constraint on the cognizance time. |
| Title | A Resource Preserved MAC Protocol for QoS Provided UWB Ad Hoc Network |
| Author | *Jiachen Zhou, Yiqing Huang, Takeshi Ikenaga (Graduate School of Information, Production and Systems, Waseda University, Japan) |
| Page | pp. 113 - 116 |
| Keyword | UWB, MAC, QoS, resource allocation, multiple access |
| Abstract | This paper proposes a resource preserved medium access control (MAC) protocol which provides Quality of Service (QoS) support for multimedia applications in ultra-wideband (UWB) ad hoc network. The proposed protocol accounts for the UWB unique characteristics while considering the QoS requirements. The evaluation results in throughputs, end to end delay, power consumption and power utilization show that, the proposed algorithms achieve a balance work between the throughputs and power consumption. |