TAILIEUCHUNG - Cellular Systems: Multiple Access and Interference Management

The total bandwidth is divided into many narrowband channels. (200 kHz in GSM) Users are given time slots in a narrowband channel (8 users) Multiple access is orthogonal: users within the cell never interfere with each other. Interference between users on the same channel in different cells is minimized by reusing the same channel only in cells far apart. | 4. Cellular Systems: Multiple Access and Interference Management Cellular Systems So far we have focused on point-to-point communication. In a cellular system, additional issues come into forefront: Multiple access Inter-cell interference management Some History Cellular concept (Bell Labs, early 70’s) AMPS (analog, early 80’s) GSM (digital, narrowband, late 80’s) IS-95 (digital, wideband, early 90’s) 3G/4G systems Four Systems Narrowband (GSM) Wideband system: CDMA (IS-95) Wideband system: OFDM (Flash OFDM) Opportunistic Communication (1x EV-DO) (later) Narrowband (GSM) The total bandwidth is divided into many narrowband channels. (200 kHz in GSM) Users are given time slots in a narrowband channel (8 users) Multiple access is orthogonal: users within the cell never interfere with each other. Interference between users on the same channel in different cells is minimized by reusing the same channel only in cells far apart. Users operate at high SINR regime The price

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