ECE DL COM 009 

EC1428 

Multiple Access Techniques and Cellular Concept Multiple access techniques : FDMA - TDMA - Spread spectrum multiple access - CDMA - SDMA - CSMA protocols - Cellular concept : Frequency reuse - Channel assignment and off - Interference and system capacity - Tracking and grade of service - Improving coverage and capacity in cellular systems. Mobile Radio Propagation Free space propagation model - Relating power to electric field - Propagation mechanisms - Reflection - Ground reflection model - Diffraction - Scattering - Link budget design using path loss models - Small scale multipath propagation - Impulse response model of a multi-path channel - Small scale multipath measurements - Parameters of mobile multipath channels - Types of small scale fading. Modulation Techniques - Diversity and Antennas Modulation techniques : Binary frequency shift keying - Minimum shift keying- Gaussian MSK - Orthogonal frequency division multiplexing - Diversity reception - Types of diversity - RAKE receiver - Basic combining methods - Base station and mobile station antennas. Speech Coding Characteristics of speech signals - Quantization techniques - Adaptive differential pulse code modulation (ADPCM)- Frequency domain coding of speech vocoders - Linear predictive coders - Selection of speech codecs for mobile communication - GSM codec - USDC codec - Performance evaluation. Cellular Standards AMPS - GSM - Architecture - Channels and frame structure - GPRS - EDGE - CDMA standards (IS-95) - Forward CDMA channel and reverse CDMA channel - W - CDMA layer architecture. - from Amzon