Sharif Digital Repository

In an operational IFM receiver, there is usually a limiting amplifier in front of the power divider, delay line, and phase correlator. The limiting amplifier can improve the sensitivity of the receiver by providing RF gain to process weak input signals. In general, a signal must reach the limiting level in order to be processed by the receiver. It is important to notice that a limiting amplifier can be used only at the input of an IFM receiver. It should not be used in other kinds of receivers because the limiting amplifier will generate intermodulation products when overlapping signals are present. Since an IFM receiver only reads one signal at a time, the limiting amplifier will not... 

Todays the use of microwave integrated circuits for military and commercial applications has gained much attention, especially with the advent of monolithic microwave integrated circuits, which provide the possibility of fabrication of amplifiers in large number, sufficient accuracy an affordable price.GaAs pHEMT process, because of good characteristics for noise and power in high frequencies, is a good choice for microwave and millimeter wave integrated circuits. A low noise amplifier is a key block in the receiver and, its noise figure and gain directly affects the sensitivity and dynamic range of the receiver. Hence, a low noise amplifier with low NF, high gain, good return loss, low... 

In recenet years the use of microwave integrated circuits for military and commercial applications has gained much more attention. The advent of monolithic microwave integrated circuits, which provide the possibility of fabrication of amplifiers in large number, sufficient accuracy an affordable price has accelerated this process. Low noise amplifiers as the first blocks in the receiver modules are such circuits that are highly regarded in this field. This block is a key block in the receiver which its noise figure and gain directly affect the sensitivity and dynamic range of the receiver. As a result, a low noise amplifier with low noise figure, high gain, good return loss, low power... 

RF Receivers are one of the main components of telecommunication systems, which can be composed of many parts and circuits according to their working frequency and application.In this thesis, the design and simulation of an X-band Receiver in 0.15um GaAs technology has been discussed. The receiver chain, in the order of receiving the signal, includes the main blocks of limiter, attenuator, low noise amplifier and mixer. It also includes a number of filters. The attenuator has two digital bits and the receiving chain filters are implemented in such a way to provide more than 20dB attenuation in the frequency band of the image signal. In this research, the limiter is implemented with a...