Re: Resolution of "info" in AM DSBFC with an eight-bit microprocessor?

jaco.versfeld@xxxxxxxxx wrote:

Hi there,

I am thinking of implementing an AM DSBFC modulator on an eight-bit
microprocessor like the PIC or maybe a Scenix microprocessor (if they
are still built). However, I am a bit concerned on the resolution
obtained with this. If one assumes 100% modulation, then the output AM
signal can be divided in 256 (2^8) levels. The signal will consist of a
positive "envelope" and a negative "envelope". This will effectively
reduce the "information" in the AM Signal to 128 levels or 4 bits. Is
my reasoning correct? Suppose I want to sample audio which I want to
use as the modulating signal, will the 4 bits at the receiver provide
enough resoultion to be still eligible? Does this mean that I can
sample the audio at 4 bits/sample?

Kind regards,
Jaco

1. An 8-bit microprocessor can do math to much higher precision than 8 bits. The only limitations are memory size to hold it, and processor speed. The processor being 8 bits just means that it can only handle 8 bits in one instruction.

2. 128 = 2^7. That's seven bits.

--

Tim Wescott
Wescott Design Services
http://www.wescottdesign.com

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