For a broadcast super heterodyne AM receiver having no RF amplifier, the loaded quality factor Q of the antenna coupling circuit is 100. Now if the intermediate frequency is 455 KHz, then determine the image frequency and its rejection ratio at an incoming frequency of 1 MHz.
Given that quality factor Q = 100
The intermediate frequency fi = 455KHz
Incoming frequency fs = 1MHz
The image frequency fsi = fs + 2fi = 1 × 106 + 2 × 455 × 103 = 1910KHz
Again we know that the relation
The image frequency rejection ratio
Explain with proper expression