| Author | Pornthip Jaroenprawat |
| Call Number | AIT RSPR no. TC-00-02 |
| Subject(s) | Mobile communication systems
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| Note | A research study submitted in partial fulfillment of the requirement for the degree of Master of Engineering, School of Advanced Technologies |
| Publisher | Asian Institute of Technology |
| Series Statement | Research studies project report ; no. TC-00-02 |
| Abstract | Digital cordless-phone systems employ TDMA-TDD under slow fading environments. Because fading affects on both uplink channel and downlink channel almost simultaneously, the occurrence of error in the uplink channel is closely correlated with that in the downlink channel. Therefore, this characteristic can be applied to predict errors in transmitted data. That is, Pre-Repeat (PR) technique for ARQ schemes is proposed by Nakamura (1998). This technique allows to retransmit the copy of data block at the transmitter side, when transmitter predicts that block of data will be corrupted without receiving the negative acknowledgement, right after the error has been detected from received signal. Pre-repeat technique can be used with any of ARQ schemes: go-back-N and selective repeat schemes. However, when a pre-repeated frame is in error and the negative acknowledgement of that frame is lost because of the error on the return channel, large delay for data may still occur. For this reason, the time-out mechanism is added in this research study to eliminate the cause of large transmission delay. In this research study, use of ARQ protocols in packet data transmission in PHS system is considered. Pre-repeat technique with time-out mechanism and only pre-repeat technique based on selective-repeat ARQ protocol are observed on Rayleigh fading channel which modeled as a Markov model. This model is accurate enough to approximate the data block success/failure on a fading mobile radio channel. The simulation results show that pre-repeat technique with time-out mechanism and only pre-repeat technique provides almost the same performance of throughput and average delay. Therefore, pre-repeat technique without time-out mechanism is the most appropriate model to adopt as selective-repeat ARQ protocol since it is simpler to implement |
| Year | 2000 |
| Corresponding Series Added Entry | Asian Institute of Technology. Research studies project report |
| Type | Research Study Project Report (RSPR) |
| School | School of Advanced Technologies (SAT) |
| Department | Department of Information and Communications Technologies (DICT) |
| Academic Program/FoS | Telecommunications (TC) |
| Chairperson(s) | Makelainen, Kimmo; |
| Examination Committee(s) | Rajatheva, R.M.AP.;Teerapat Sanguankotchakorn; |
| Scholarship Donor(s) | Self-Support; |
| Degree | Research Studies Project Report (M.Eng.) - Asian Institute of Technology, 2000 |