What is the difference between am-dsb and am-ssb?

Answer 1

Am- DSB stands for Double or Duplex Side Band Am- SSB- amplitude modulation, which is what Am means, Single-Side-Band, sideband sometimes written as one word but abbreviated phonetically as SSB. SSb is widely used in amateur radio and some forms of CB as well. the concept is related to the much older, and still viable idea of Bandspreading, or Bandspread where the tuning is split over two dials or a subdial for the fine-tuning harmonics. applied to receivers only. Get some old electronics magazines from the thirties from Lindsay"s publications, angled at the hobbyist they explain things as they go along. the Gernsback l934 Short wave manual is good technical theory and also has reviews and circuit diagrams of many then current radio gear, great fun for browsing.=and technically correct.

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Normal a.m. transmission has a carrier and two identical sidebands, the upper and lower. That's a.m. d.s.b. (double sideband).

The sum of the power in the two sidebands can't exceed half that of the carrier.

For example, a 100W carrier modulated to 100% will have 25W in each sideband.

It is possible to achive better efficiency by suppressing the carrier, which means that half the transmitted power will be in each sideband. That's still d.s.b., with the addition of s.c. to indicate the difference.

A further increase in efficiency can be achived by also suppressing one of the sidebands, so all of the transmitted power is in that sideband. That is what is normally referred to as s.s.b., but more correctly it's s.s.b. s.c.