15-02-2013, 11:57 AM
Resequencing Analysis of Stop-and-Wait ARQ for Parallel Multichannel Communications
Resequencing Analysis.doc (Size: 25.5 KB / Downloads: 54)
Abstract:
Under the assumption that all channels have the same transmission rate but possibly different time-invariant error rates, we derive the probability generating function of the resequencing buffer occupancy and the probability mass function of the resequencing delay. Then, by assuming the Gilbert–Elliott model for each channel, we extend our analysis to time-varying channels. Through examples, we compute the probability mass functions of the resequencing buffer occupancy and the resequencing delay for time-invariant channels. We analyze trends in the mean resequencing buffer occupancy and the mean resequencing delay as functions of system parameters.
Algorithm / Technique used:
Gilbert–Elliott Model.
Algorithm Description:
Very simple mode: channel states
1. Good state: signal above “threshold”, BER is virtually Zero
2. Poor state: “signal outage”, BER s ½, reciver falls out of sync, etc.
Markov model approach.
1. Memory less transistions.
2. Exponential distribution sojoum time.
Existing System:
An analytical approach for analyzing the mean % packet delay and mean queue length at the transmitting terminal in % wireless packet networks using the selective repeat (SR) automatic % repeat request (ARQ) scheme to control the errors introduced by the % non-stationary transmission channel. Each transmitting terminal is % modeled as a discrete time queue with an infinite buffer. The% non-stationary transmission channel is modeled as a two-state Markov % chain. Comparisons of numerical predictions and simulation results are % presented to highlight the accuracy of the proposed analytical approach
Proposed System:
We consider a multi-channel data communication system in which the stop-and-wait automatic-repeat request protocol for parallel channels with an in-sequence delivery guarantee (MSW-ARQ-inS) is used for error control. We evaluate the resequencing delay and the resequencing buffer occupancy, respectively. We expect that the modeling technique and analytical approach used in this project can be applied to the performance evaluation of other ARQ protocols (e.g., the selective-repeat ARQ) over multiple time-varying channels.