transmitting based on a received signal - LabVIEW + NI USRP N210

[Insiderbe]

Hi again,

I'm working on a project to transmit a signal on specific channel at maximum power, based on a received signal. (minimum bandwidth)
As an example, i'm using the frequency range of walkie talkies PMR446 ( 446.00625 MHz -> 446.09375 MHz) I'd like to check the full band, receive 1 channel and then react (=transmit) full power on that same frequency.

I can already receive the signal of walkie talkie, by using de Rx freq 446.00625MHz  (channel 1). When the program does a peak detection (i should get the amplitude and specific frequency). The freq is given in

--> now: in my spectrum analyser: i'd like my "offset from carrier" to be 0 at the peak... now it's at 500k ? It's not showing anything lower than 0

-->I'd like to change the bandwidth so he can check the 8 channels...

I'd like to use STATES (case structures) but I can't extract the info from the Rx to the Tx

In the Tx cycle:

-transmitting a normal sine-wave should work instead of using a modulation (For PMR446 it's a level 4 FSK), in order to jam that whole channel ( 2 times 12.5kHz )
Anyway, if i try to sent a signal using an example transmitter FM.VI, changing the modulation to FSK ofcourse, my PMR's don't receive anything...
(while transmitting to a radio frequency, with FM modulation, that works)

-I want to use the frequency from inside the loop of the Rx cycle.. but the program does not accept that 😕
-I only have 1 VERT400 Antenna, is it possible to use the same antenna channel (RX1 or TX1)?

Could you give my some advice / or other possible solutions please? 🙂

available hardware :
NI USRP N210 (rev 4) with WBX 50-2200 Rx/Tx and AE VERT400

NI USRP N210 ( rev 4 )with CBX 1200-6000 MHz Rx/Tx (40 MHz) and 2xAE VERT900 and AE VERT2450
connection via gigabit

PC: W7 64bit, i7-2600 @ 3.4GHz, 4Gb RAM

[muffin.vi]

Insiderbe,

Have you seen the record and playback example for the USRP? The demo was done with walkie-talkies, so it might be very similar to what you're doing.

[Insiderbe]

not yet, thanks, i'll try this first thing in the morning! 🙂

[Insiderbe]

The tutorial was useful, but still having issues completing the program

peak detection isn't working fully, the shift registers don't remember the values? :s