Explain the architecture of TDMA?

NA-TDMA architecture:

The NA-TDMA architecture is similar to GSM architecture. The only difference is that in NATDMA, there is only one common interface, which is the radio interface as shown in Fig. 5. The NA-TDMA uses the intelligent network. All the components such as HLR, VLR, AUC, and EIR are the same as used in GSM. In developing the NA-TDMA system, there were two phases:

First phase: To commonly share the 21 set-up channels that are used for the analog system. The first-phase system is only for voice transmission. Both modes, AMPS and digital, are built in the same unit. The handoff procedure has to take care of the following four features:

1. AMPS cell to AMPS cell

2. TDMA cell to TDMA cell

3. AMPS cell to TDMA cell

4. TDMA cell to AMPS cell

Second phase: (1) generate new digital set-up channels (they were in the voice band) to access to TDMA voice channels so that a digital stand-alone unit can be provided and (2) specify a data-service signal protocol for transmitting data.

NA-TDMA system architecture