Analysis of dual-hop OFDM relay system with subcarrier mapping in rayleigh and nakagami-m fading | |
| Author | Shah, Raza Ali |
| Call Number | AIT Diss. no.ICT-15-01 |
| Subject(s) | Orthogonal frequency division multiplexing Rayleigh model |
| Note | A dissertation submitted in partial fullfilllment of the requirements for the degree of Doctor of Philosophy (Ph.D.), in Information and Communications Technology, School of Engineering and Technology |
| Publisher | Asian Institute of Technology |
| Series Statement | Dissertation ; no. ICT-15-01 |
| Abstract | In this dissertation, the performance of a dual-hop OFDM amplify-and-forward (AF) relay system with subcarrier mapping (SCM) is analyzed in Rayleigh as well as Nakagami- m fading channel models. The bit-error rate (BER), ergodic capacity, outage probability and outage capacity performances of the system are compared with ordered subcarrier pairing schemes, i.e., best-to-best (BTB) SCM, well known for capacityenhancement and worst-to-best (WTB) SCM, well known for BER minimization. The BER performance of OFDM AF relay system is analyzed in a multipath Nakagami-m fading channel. It is veri ed through analytical and numerical proofs that the parameter m translates to the new fading severity parameter m0 in case of dual-hop OFDM relay system and the range 1 2 m < 1 corresponds to 1 2 < m0 < 2 for large number of resolvable channel paths L. For multipath Nakagami-m fading channel model between source-to-relay (S-R) and relay-to-destination (R-D) links, closed-form expressions are derived for the probability density function (PDF) and moment generating function (MGF) of end-to-end SNR for integer as well as non-integer values of m, hence, m0. The classical PDF and MGF based approaches are used for the comparison of system-performance with WTB SCM and BTB SCM schemes on the basis of BER. The e ect of m and L on the BER variations is thoroughly investigated. The ergodic capacity performance of dual-hop OFDM AF relay system for ordered SCM schemes is then examined. Jensen's inequality is solved to derive the close-form expressions for ergodic capacity. The performance analysis on the basis of system's ergodic capacity is then described. Outage capacity, which is more exible and realistic capacity measure, and considers higher moments of end-to-end SNR, is then analyzed. Closed-form expressions for the outage capacity of the system with WTB SCM and BTB SCM are derived for Rayleigh as well as Nakagami-m fading multipath channels f{u100000}or each hop. Two special cases of Nakagami-m fading, i.e., one side Gaussian fading m = 1 2 and Rayleigh fading (m = 1) are, speci cally, focused. The outage probability, which is an important performance metric, is then analyzed. Closed-form expressions are derived for the outage probability of the system in terms of CDF and PDF of end-to-end SNR of hop-1 and hop-2 respectively. The performance of the system with ordered SCM schemes is compared for a wide range of SNR in multipath Rayleigh as well as Nakagami-m fading channels. The e ect of m and L on the variations of outage probability is thoroughly investigated. Various analytical proofs with illustrations are presented to show the accuracy and validity of our derived expressions. The proximity of theoretical and numerical results validates our work and compares the performance of dual-hop OFDM relay system with ordered SCM schemes for various performance measuring parameters. |
| Year | 2007 |
| Corresponding Series Added Entry | Asian Institute of Technology. Dissertations ; no. ICT-15-01 |
| Type | Dissertation |
| School | School of Engineering and Technology (SET) |
| Department | Department of Information and Communications Technologies (DICT) |
| Academic Program/FoS | Information and Communication Technology (ICT) |
| Chairperson(s) | Rajatheva, R. M. A. P.; |
| Examination Committee(s) | Poompat Saendudomlert;Mongkol Ekpanyapong; |
| Scholarship Donor(s) | Higher Education Commission (Pakistan);Asian Institute of Technology Fellowship; |
| Degree | Thesis (Ph.D.) - Asian Institute of Technology, 2015 |