Question

Consider a superheterodyne receiver designed to receive the frequency band of 800 MHz to 2000 MHz. A dual-mode system uses this receiver to accept either 850 MHz or 1900 MHz signals. What is the range of frequencies generated by the local oscillator for the receiver? is it possible for the receiver to receive both the desired and image stations when tuned to the desired frequencies? If yes, find the image frequencies. Use an intermediate frequency of 500 MHz.

Answer 1

The range of frequencies generated by the local oscillator for the receiver in a dual-mode system can be calculated by adding and subtracting the intermediate frequency (IF) from the desired frequencies. Yes, it is possible for the receiver to receive both the desired and image stations when tuned to the desired frequencies. The image frequencies can be found by subtracting or adding twice the IF to the desired frequencies.

Step-by-step explanation:

The range of frequencies generated by the local oscillator for the receiver in a dual-mode system can be calculated by adding and subtracting the intermediate frequency (IF) from the desired frequencies. In this case, the local oscillator would generate frequencies of 350 MHz and 1400 MHz for the 850 MHz and 1900 MHz signals, respectively. These frequencies are obtained by subtracting the IF (500 MHz) from each of the desired frequencies.

Yes, it is possible for the receiver to receive both the desired and image stations when tuned to the desired frequencies. The image frequencies can be found by subtracting or adding twice the IF to the desired frequencies. For the 850 MHz signal, the image frequencies would be 150 MHz and 1950 MHz. For the 1900 MHz signal, the image frequencies would be 900 MHz and 2400 MHz.