The control unit contains handset with speaker and microphone. It also contains a complete touch tone dialing circuit.
It is operated by a separate microprocessor drives the LCD display and other indicator .It also implements all manual control functions .
The microprocessor memory permits storage of often called numbers and an ..
The logical unit contains the main control circuitry for the cellphone unit. The logical unit consists of a CPU, RAM, ROM, I/O interface circuit and control logic. NAM (Number
Assignment Module) is a programmable read only memory (PROM).The NAM holds the Mobile Identification
Number (MIN) i.e. the telephone number of the mobile phone.
The serial data comes from the MTSO. The bit rate of this signal is 10kbps. The MTSO keeps a full control over all the cell phones using this serial data.
This signal controls the transmitting and receiving frequencies and transmitted power.
The MTSO checks the received signal strength at the mobile by observing the RSSI signal and adjust the transmitted power level. Control signals from control logic section are applied to transmitter and receiver section of mobile unit
