Project rules: Wireless Communication MATLAB Project

Transcription

1 This document provides an outline for a MATLAB project. You are expected to investigate, in detail, methods related to solving the problem. There is a substantial design element to the project, and a quantitative evaluation of the performance of the proposed methods must be performed and presented. Project rules: You may work in pairs if you so wish (max=2 students). Your final report must be a comprehensive report, but with maximum of 10 pages. Your final report must include a CD which contain all MATLAB files but classified in folder named by section. Any figure of the result must be accompanied by comments of your words. Any attempt to copy from the Internet will face severe punishment. Any attempt to copy from any colleges will face severe punishment for both of source and destination. Deadline 17/12/2011, no excuse.

2 Introduction: Figure 1 shows a simplified block diagram of a wireless communications link. The transmitter processes the data as follow: A/D, modulate, D/A, then transmit it through the channel. The other functions of the transmitter, such as source coding and channel coding, is beyond the scope of this project. Here, we will deal with several model of the wireless channel, such as AWGN and fading channel (fast fading, flat fading, Etc). Certainly, the receiver will reverse the operation of the transmitter, and then produce the signal to information sink. Information Source Transmitter Wireless Channel Receiver Information Sink Figure 1: Simplified block diagram of a wireless communications link In most cases, the goal of a wireless link is the transmission of information from an analog information source (microphone, video camera) via an analog wireless propagation channel to an analog information sink (loudspeaker, TV screen); so, here we will simulate our schemes to process audio and image files, not a random data. Notes: Deal with test image file as a gray scale file not a RGB file, so it must be m*n*1 not m*n*3. Use a sufficient quantization level in both cases (wave and image). Objectives: Be familiar with the simulation of whole wireless communications link using real data (recorded voice file). Be familiar with the simulation of many wireless channel types (AWGN, flat fading channel, etc) Be familiar with the simulation of Rx. Spatial diversity under many combination schemes such as selection, switching, and MRC.

3 The tasks: 1. Basic background from digital communications course: Here, you are asked to simulate the systems under the assumption there is no noise or fading in the channel, (this scheme is used to test the functions of TX. and RX) Simulation parameter : Information source: in the attachments (testimg and testwav) Note: you can use the built in function of the MATLAB This simulation has the following features: The ability to change the modulation type (PSK, QAM). The ability to change the modulation order (m=8,16) Just one MATLAB file for the case of voice named by main04wav.m and just one MATLAB file for the case of image by main04img.m. 2. Simulation over AWGN channel: Modify the previous MATLAB files (main04img.m and main04wav.m) to have AWGN channel between the transmitter and the receiver, and then simulate the BER for the given EB/N0 range (for loop). Simulation parameter : EB/N0=0:3:30dB channel. In report: One figure for the relation of BER over EbN0 range QAM and PSK modulation for m= 8 and 16. Two figure show the reconstructed EbN0=0dB, and 6dB Your comment

4 In CD: MATLAB files: main14img.m and main14wav.m, both of them simulate BER over EbN0 range given. Four audio files for the received data at EbN0=0, 6, 12, and 24. (Named it by wav_awgn_0.wav, wav_awgn_6.wav, etc). Four image files for the received data at EbN0=0, 6, 12, and 24. (Named it by img_awgn_0.jpg, img_awgn_6.jpg, etc). 3. Simulation over flat fading channel: Modify the previous MATLAB files to have fading+awgn channel between the transmitter and the receiver. Named it by (main24img.m and main24wav.m) Here, the fading is Rayleigh block fading. channel. Repeat same required as previous in (2) (but in CD named it by fad instead of awgn. Compare between the results in case just AWGN channel and the case of flat fading channel. 4. Simulation of space diversity over fading channel in case of RSSI scheme: Modify the previous MATLAB files (main24wav.m and main24img.m) to have additional spatial branch (space diversity) for the case of 2, and 4 Rx. antennas, and named it by main34rssi2wav.m, main34rssi4wav.m, main34rssi2img.m, main34rssi4img.m Use RSSI scheme for all cases. channel or model the diversity

5 Repeat same required as previous in (3) (but in CD named it by rssi_div#ofrx.antenna instead of fad, it would be eight audio files and eight images,. Compare between the results in case of no diversity and the cases of 2 and 4 Rx. space diversity. 5. Simulation of space diversity over fading channel in case of MRC scheme: Repeat part (4) but use MRC scheme instead of RSSI selection scheme. Repeat same required as previous in (3) (named it by mrc_div#ofrx.antenna instead of fad, but it would be eight audio files and eight images) Compare between the results in case of RSSI scheme and the cases of MRC scheme.