Mobile Handset Design

10

Anatomy of a GSM Mobile Handset

10.1 Introduction to the GSM Handset

The GSM mobile handset has evolved over a period of time and its efficiency with respect to size, weight, complexity, application support, performance, and battery life has improved. In Chapter 1, we briefly discussed the internal components of any mobile phone. The basic phone architecture and the associated peripherals such as display (LCD), keypad, speaker, microphone, and so on, remain almost the same with respect to the air interface technology or mobile standard used. However, based on the particular mobile standard, the front-end RF unit, the baseband processing unit, and the protocol stack used (especially up to layer-3) will be different.

As discussed in Chapter 1, a GSM mobile contains several components, such as a microphone, speaker, LCD display, keypad, battery, LED, baseband processors, CODEC, SIM card, memory, RF unit, antennas, connectors, and so on. Generally only a few ICs are mounted in the PCB to carry out these functional activities. In Figure 10.1 an IC mounted PCB of a typical GSM mobile phone is shown as an example.

Nowadays, as a result of technological advancements, higher integration is possible which iswhy only a few ICs are sufficient to make a complex mobile phone. A single-chip solution (system-on-a-chip, SOC) is also available, which will not only reduce the size of the device but also reduce the cost and battery consumption. Deep submicron CMOS technologies enable sophisticated ...