Just the status report from the work done the past couple of weeks on
OFDM. With Matt E., Bob McGwier, and Eric B., we successfully
transmitted and received OFDM over the air with BPSK, QPSK, and 16QAM. I
have merged the code into the trunk so others can use it, though I
currently restricted the subcarrier modulations to use only BPSK or QPSK
(M-QAM will be coming soon I hope). It’s not complete; specificially, it
lacks an adaptive equalizer over the entire packet and channel coding.
Other features should be coming over time, too.
If you’re interested, and for the good of the community, I have posted
the presentation I gave last week to the [email protected] Symposium about the
implementation details of the system. This includes the block-diagram
representations of the flow graphs for the transmitter, receiver, and,
most importantly, the synchronizers used in the system. I have made it
available in both PPT and PDF format (the PPT opens just fine in the
latest version of Open Office for those without MS Office). You can find
it under the Presentations link on the front page of Trac (Johnathan,
Eric, if you have a better place to put this kind of information, let me
know; this seemed like a good place to start).