Yes with 40 dB attenuation. Somehow I didn't see your post.
Marcus D. Leech wrote: > > On 10/06/2010 11:41 AM, sirjanselot wrote: >> I meant TXA to RXB. >> >> sirjanselot wrote: >> >>> Thank you for your response. >>> >>> I've tried gr sounder but from the looks of it, it is only accurate when >>> you use the LFRX/TX or the RFX boards. >>> >>> I have a WBX transciever and when I tried it on my first shot measuring >>> the channel coefficients by directly connecting the output of my TXA to >>> my >>> RXA, the length of the channel was 32760 coefficients!!!! >>> > When you say "directly', you mean through a minimum 30dB attenuator, > correct? The output power of > the transmitter can easily damage the LNA in the receiver if directly > connected, and at the > very least, will cause serious clipping. > > >>> I haven't been able to figure out how to read the output.dat of the >>> gr-sounder yet but this is what is showing me on debugging mode. >>> >>> It also keeps giving me this warning message: >>> gr_buffer::allocate_buffer: >>> warning: tried to allocate >>> 4 items of size 32760. Due to alignment requirements >>> 512 were allocated. If this isn't OK, consider padding >>> your structure to a power-of-two bytes. >>> On this platform, our allocation granularity is 4096 bytes. >>> >>> Any thoughts? >>> >>> Thank you. >>> >>> >>> Martin Braun-4 wrote: >>> >>>> On Tue, Oct 05, 2010 at 11:43:53AM -0700, sirjanselot wrote: >>>> >>>>> Hello, >>>>> >>>>> I'm trying to figure out how to measure the impulse response of a >>>>> channel >>>>> its coefficients. >>>>> >>>> Hello sirjanselot, >>>> >>>> the channel sounder which is part of GNU Radio works, but has no >>>> synchronisation or anything--so you have no direct means of averaging >>>> taps. Perhaps you can give it a bash, though. >>>> >>>> Cheers, >>>> MB >>>> >>>> -- >>>> Karlsruhe Institute of Technology (KIT) >>>> Communications Engineering Lab (CEL) >>>> >>>> Dipl.-Ing. Martin Braun >>>> Research Associate >>>> >>>> Kaiserstraße 12 >>>> Building 05.01 >>>> 76131 Karlsruhe >>>> >>>> Phone: +49 721 608-3790 >>>> Fax: +49 721 608-6071 >>>> www.cel.kit.edu >>>> >>>> KIT -- University of the State of Baden-Württemberg and >>>> National Laboratory of the Helmholtz Association >>>> >>>> >>>> >>>> _______________________________________________ >>>> Discuss-gnuradio mailing list >>>> [email protected] >>>> http://lists.gnu.org/mailman/listinfo/discuss-gnuradio >>>> >>>> >>>> >>> >>> >> > > > -- > Principal Investigator > Shirleys Bay Radio Astronomy Consortium > http://www.sbrac.org > > > > _______________________________________________ > Discuss-gnuradio mailing list > [email protected] > http://lists.gnu.org/mailman/listinfo/discuss-gnuradio > > -- View this message in context: http://old.nabble.com/How-do-you-measure-the-channel-impulse-response--tp29890077p29900374.html Sent from the GnuRadio mailing list archive at Nabble.com. _______________________________________________ Discuss-gnuradio mailing list [email protected] http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
