Re: Setting tx_gain > 20 dB => no effect? (USRP2, XCVR2450)

GNU Radio
1

Hi Jeffrey,

thanks for the advice. The standard power of USRP2 should be enough
for me, if I really get it :slight_smile:
In the specifications for XCVR2450 it says 100mW or 20 dBm.
The jamming is already working, but a bit more power would be fine :wink:

Yesterday I moved the micaz node around my USRP2 to find the maximum.
I couldn’t get more than -13 dBm even with my micaz nearly touching
the antenna of the USRP2.

I used 30 dB gain at sink (just to be safe) and an amplitude of 1
again (so 21+ dB gain would have been about equal then).

Is there something I could do softwarewise to get more than about -13
dBm? (another amplitude, samp_rate, interpolation …) Doing something
wrong hardware or softwarewise? Perhabs the micaz RSSI value isn’t
exact enough?
I don’t expect exactly 20 dBm at the micaz, but it should be more than
-13 dBm with the micaz just about 1cm distance to antenna, shouldn’t
it?

Regards,
Sven Oliver

2

the antenna of the USRP2.
it?

For an isotopic radiator received power is proportional to the inverse
cube of the distance.
Plus your receive antenna won’t be 100% efficient, etc. For ordinary
radios a received signal
of -13dBm is thundering strong.

–
Principal Investigator
Shirleys Bay Radio Astronomy Consortium