DESIGN OF LOW POWER MOBILE TRANSMITTER

The objective of this project is to design a power amplifier for a new two way mobile
radio product being launched by Motorola. Two-way mobile radio consists of a
transmitter, receiver and a voltage-controlled oscillator. Mobile radios usually have
transmitter whose power output ranges from 1 W to 50 W. Design of transmitter lineup
for mobile radio involves the design of appropriate matching network for driver
and power amplifier. The power and voltage control of these devices are equally
important. Designing a mobile radio transmitter is regarded tricky due to difficulty in
getting a robust transmitter that is stable with minimum oscillation.
In this work, the design is attempted usmg Advanced Design Simulator
(ADS). The design simulation provides accurate simulation on harmonic filter and
antenna switch. 50 ohm matching networks have also been designed and simulated
using ADS and it gives close approximation to the specifications. The radio has since
been prototyped and tested. The evaluation and testing of the radio has been carried
out and it satisfies the specifications that are set by the Telecommunication Industry
Association (TIA). Some minor optimization has also been performed to improve the
radio performance. Eventual product is a transmitter line up that function well today.
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