Electronics and Communication Engineering - Communication Systems - Discussion

Central frequency should be 1000 khz.
All other frequency should be 1000+-fm.
Due to it the answer should be 998kHz.

According to option, it is AM multitone technique. I agree @Arnab Bhattacharya.

Here, not mention which type of modulation with a career. If we let it is AM, then obviously least frequency is 998kz (1000-2=998KHz).

I am not getting this. Please explain it.

@Arnab Bhattachary.

You are absolutely right.

I also agree for 998khz as it's a least frequency in AM.

Please give the explanation in an understanding manner.

Please give explaination properly.

D is right answer given answer B is wrong because question is asking least frequency that is present in the output means in the frequency spectrum least frequency present is 1000-2 =998 KHz so D is right answer.

If there are six possible frequency such as-1000000+300=1000300,1000000+800=1000800, 1000000+2000=1002000.
Now next,1000000-300=999700,100000-800=999200,
1000000-2000=998000.
Now least value of frequency is-998khz. And greatest value of frequency is 1002khz.
Then according to question that least value of frequency which is not likely present in the o/p is -1000khz because in the range from998khz to1002kz, the 1000khz is not shown hence a/q and given options 1000khz is correct.

This is an example of FM , in which higher frequency components gets attenuated (i.e, less probability of occurence).

Therefore fc-fm= -1000 (lsb higher frequency component) will be the answer as per the given option, even fc+fm= 3000 will also not occur but not in the option.