GSM Interview Question:

What is channel coding in GSM Technology?

Submitted by: Muhammad

★ The data rate for the radio channel is 270 kbps
★ The data rate is split into 8 full rate or 16 half rate traffic channels, along with signaling channels
★ In order to have the maximum chance for detecting and correcting errors, the code is complex in a typical propagation path
★ Forward Error Correction is applied in order to get the speech coder encryption, coding and interleaving in a sophisticated way
★ The data is sent as bursts in 577 mus time slots. Each contains 116 encrypted bits
★ Every TDMA frame consists of 8 or 16 time slots
★ Transmit time slots are staggered, so that at some instant the mobile station will not receive the same instants while transmitting, which enables the simplifying the filtering requirements
★ At least one spare slot between transmit and receive is available with this scheme.
Submitted by: Muhammad