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Being the interface circuits that process radio frequencies for Radars, depending on applications, there are different types of Radar front ends that can be selected to be most suitable for the requirements. Radar front ends may be categorized by the operating frequencies, the way they interface with antennas , and the way they process the information. Some generic Radar front ends are described here.

MIMO (Multiple-Input Multiple-Output) Radar front ends are similar to the phased-array Radars in the sense that they are both multiple-antenna systems. MIMO Radars utilize special digital signal processing techniques on a multiple units of Radars to generate a virtual antenna array. Basically, a bigger virtual array representing more receive and transmit units can be created from a smaller number of actual receive and transmit units. Therefore, by processing the mutual signals between multiple units, a more powerful Radar system resulting from an array of transmitters and receivers can be realized without physically using the corresponding number of receivers and transmitters. A basic diagram of a MIMO Radar front end is shown in Figure 3.

Pulsed Radar is a time-domain Radar system, in which a high-power and short electrical pulse is are transmitted and the reflected pulse from an object is detected. By processing the time between the transmitted pulse and the reflected pulse, the distance of that object can be measured. The system may start the measurement of the time at the beginning of the transmitted pulse and finished finish counting the time after detecting the reflected signal. As shown in the basic diagram of Figure 4, the pulse control unit generates a square-wave pulse where the pulse former is used to re-shape to pulse to be suitable for transmission. In the receiver part, the same pulse shape is required as a template to down-convert the received pulse to be suitable for the sample and hold (S&H) circuit.