Data transmission in Mobile phones
- Thread starter sagarin
- Start date
I can sum it up in one word. Multiplexing
There have been several types of Multiplexing used in mobile phone communications:
1st Gen used Frequency Division Multiplexing - simple, and had a long symbol duration making it less susceptable to inter-signal interferences; however had a low bandwidth efficiency (expensive) and suffered from an issue know as the near-far-problem which caused severe near channel interference.
2nd Gen uses Time Division Multiplexing - simple in terms of time-slot allocation and power control at the base-station; however had low symbol duration makin it sensitive to inter-signal interference, required guard bands wasting bandwidth and there is a hardware overhead administrating the system timing (which becomes an increasing problem as more people use the network).
3rd Gen uses Code Division Multiplexing - robust system that is resistant to frequency sensitive fading, has flexible and high date rates, and is less sensitive to synchronisation requirements; however this comes at the cost of increased system complexity and bandwidth (which as you should know is very expensive).
Dave
1st Gen used Frequency Division Multiplexing - simple, and had a long symbol duration making it less susceptable to inter-signal interferences; however had a low bandwidth efficiency (expensive) and suffered from an issue know as the near-far-problem which caused severe near channel interference.
2nd Gen uses Time Division Multiplexing - simple in terms of time-slot allocation and power control at the base-station; however had low symbol duration makin it sensitive to inter-signal interference, required guard bands wasting bandwidth and there is a hardware overhead administrating the system timing (which becomes an increasing problem as more people use the network).
3rd Gen uses Code Division Multiplexing - robust system that is resistant to frequency sensitive fading, has flexible and high date rates, and is less sensitive to synchronisation requirements; however this comes at the cost of increased system complexity and bandwidth (which as you should know is very expensive).
Dave
