In this chapter we will discuss in brief about radio astronomy and the earth rotation aperture synthesis technique which is used in the Giant Meterwave Radio Telescope. We will also discuss about the images from a single dish radio telescope and how radio interferometry and aperture synthesis techniques are useful for getting images of better resolution.
In another section we will discuss about the Giant Meterwave Radio Telescope (GMRT), with its details like the GMRT array, antennas and feeds, the receiver system, the correlator system and the software system. In the correlator system we will discuss in brief, the delay-dpc subsystem, FFT (Fast Fourier Transform) subsystem and Multiplier and Accumulator subsystem. In the area of software, we will discuss about the ONLINE software, data acquisition software and the offline data analysis software.