Abstract:
In this thesis a broadband power amplifier has been designed,
fabricated and tested operating at X-Band. The Amplifier is designed in hybrid
cascade configuration consisting of three stages, implemented on Roger’s
substrate having ϵr of 3.38. The exact frequency of operation is between 9.3-
9.9 GHz. The cascade comprises of two Low Noise Amplifiers and a main high
power amplifier device (Field Effect Transistor) along with a Microstrip
coupled line band pass filter and an isolator at the output end. The achieved
flat Gain is around 42dB with power output Gain of 28-30 dBm and noise
figure of 2.4 dBs. Power output fluctuates between 28-30 dBm levels
depending upon the frequency being hopped by Radar. The power aided
efficiency of the amplifier comes out around 13%, which is acceptable for
class A configuration. The center frequency of the coupled line band pass filter
is at 9.65 GHz and it allows a band of 9.3-9.9 GHz and rejects other
frequencies.
The design and simulation of power amplifier has been carried out with
Advance System Design software (ADS) by Agilent. The circuit layout has been
created using Protel software and finally fabrication was carried out. Lab
testing of the circuit has been carried out using spectrum analyzer. The
simulated parameters have been verified through the actual circuit testing,
this has validated the correctness of our design. After completion the thesis
has been successfully implemented on a frequency hopping Radar (32 x
Frequencies random hopping).
