Andy, Grants explanation of I/Q modulation is excellent.
Perhaps your conversation involved using complex sampling (I/Q) to double the bandwidth compared to simple sampling. The usable bandwidth is limited to about one half the sampling frequency (google NYQUIST). When looking at faster convertors you reach a point where doubling the conversion rate more than doubles the cost, or a convertor that fast may not exist. By using two simultaneous convertors, sampling the I and Q signals, the usable bandwidth is doubled. If two channels are available, there is a way to double the data rate without involving the I/Q signals. Of course I am speculating about the nature of your conversation, so I may be way off. Hope this helps. '73 de Ed N8BBQ _______________________________________________ Sent via [email protected]. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
