Department of Electrical and Computer Engineering
M.S. Thesis Abstract
Parallel Simulator of Wireless Networks
This thesis describes the Wireless Propagation and Protocols Evaluation Testbed (WiPPET), a virtual testbed for parallel simulation of wireless networks. Written in the Telecommunications Description language (TeD) developed at Georgia Tech, WiPPET provides a platform to model wireless networks at multiple time scales. The current implementation supports call level and packet level time scale granularity.
Session level WiPPET has radio propagation models for distance loss and shadow fading and radio resource management modules for call admission, uplink power con- trol, and handoff. Six handoff algorithms, including three standards-based algorithms (AMPS, IS-136, GSM) plus three others from the literature, are supported. Session level WiPPET evaluates radio resource management protocols by measuring call block- ing, call dropping, average number of handoffs per call, and other statistics at the time scale of a call. The simulator is found to be consistent with results from the earlier WINLAB Mobility And Dynamic Resource Allocation Simulator (MADRAS).
For packet level WiPPET, the propagation model includes distance loss, short scale (Rayleigh) and long scale (shadow) fading. The simulator provides multiple samples of the instantaneous signal to interference ratio (SIR) during each packet. The packet error rate (PER) can be determined from SIR samples and is used to evaluate the performance of data-link layer protocols in interference and fading environments. A current study uses packet level WiPPET to assess PER in the Cellular Digital Packet Data (CDPD) standard.
This thesis discusses two methods to parallelize the interference calculation: geographic parallelization, and radio channel parallelization. These two methods are experimentally evaluated in terms of simulation scalability, efficiency and execution speedup.
Thesis Director: Professor Roy Yates