I'm aware of the definition of orthogonality. The document originally referenced that defined Pactor-3 made it obvious that the sidebands overlapped. My email was to make the point that the Pactor-3 subcarriers have to be orthogonal to make it work and therefore Pactor-3 must be OFDM -- something that others disputed.
73, John KD6OZH ----- Original Message ----- From: Rick Karlquist To: digitalradio@yahoogroups.com Cc: digitalradio@yahoogroups.com Sent: Sunday, November 26, 2006 07:28 UTC Subject: Re: [digitalradio] Re: OFDM data is Emission Designator D1D You are still confused about the definition of "orthogonal". Before Orthogonal Frequency Domain Multiplex (OFDM), there are (Non-orthogonal) Frequency Domain Multiplex (FDM). It too used each sub carrier to send an independent stream of bits. The sub carriers were NOT orthogonal. They didn't need to be because their sidebands did not overlap. OFDM squeezes more carriers into the same space by making the carriers and their modulation orthogonal to their next door neighbors. This allows some overlap. The subcarriers in Pactor-3 may indeed be orthogonal (I don't know) but that cannot be deduced from the fact that they carry independent streams of bits. Rick N6RK John B. Stephensen wrote: > I should have said that the subcarriers must be orthogonal because > Pactor-3 uses each subcarrier to send an independent stream of bits. In > someone else's email they verified that the subcarriers are indeed > orthogonal. > > 73, > > John > KD6OZH > > ----- Original Message ----- > From: Rick Karlquist > To: digitalradio@yahoogroups.com > Cc: digitalradio@yahoogroups.com > Sent: Wednesday, November 22, 2006 19:49 UTC > Subject: Re: [digitalradio] Re: OFDM data is Emission Designator D1D > > > John B. Stephensen wrote: > > its orthogonal because the state > > of each subcarrier is independent of the state of the others. > > John > > KD6OZH > > That is NOT the definition of "orthogonal". > > Rick N6RK > > > >
