I'm working on frequency hopping using GNU Radio and USRP N210 as a function of Cognitive radio. Here, I have a .csv file which has the availability of channel to use among 4 frequency channels in a binary format like:
CH0 CH1 CH2 CH3
(900) (910) (920) (930) (Mhz)
1 0 0 0 (for 10 rows)
0 1 0 0 (for the next 10 rows)
0 0 1 0 (for the next 10 rows)
0 0 0 1 (for the next 10 rows)
and each row is the spectrum occupancy for 1 second interval.
I have to create a GNU Radio custom block to send timed PMT messages to the command input of USRP source to HOP THE FREQUENCY.
I'm unable to understand how to use the "Message Passing API" to create this block using "GR-MODTOOL" that needs to send a "tune_request" as a message to change the "freq" at the UHD: USRP SOURCE. Please let me know if I'm missing something here that will help me do this or what I need to do, to code such a bloc function.
I have read through the message passing API (msg_handler function) and the formats for the tune request, but it is hard to figure this out.
SOMEBODY, PLEASE HELP ME TO DO THIS.
Any kind of help with this would be of great value to me and is wholeheartedly appreciated.
Thank you very much in advance.
Aravind Deshikh. V