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<DIV>OK.</DIV>
<DIV>Thank you and Sylvain very much!</DIV>
<DIV> </DIV>
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<DIV><SPAN>jiangwy</SPAN></DIV>
<DIV> </DIV>
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<DIV><B>From:</B> <A href="mailto:alexander.chemeris@gmail.com">Alexander
Chemeris</A></DIV>
<DIV><B>Date:</B> 2013-06-07 18:12</DIV>
<DIV><B>To:</B> <A href="mailto:wyjiang@ljshuoda.com">wyjiang</A></DIV>
<DIV><B>CC:</B> <A href="mailto:umtrx@lists.osmocom.org">UmTRX</A></DIV>
<DIV><B>Subject:</B> Re: Time to Switching Frequence</DIV></DIV></DIV>
<DIV>
<DIV>Jiang,</DIV>
<DIV> </DIV>
<DIV>It's not tested. LMS6002D chip by itself has quite short tuning time,</DIV>
<DIV>but the current host and FPGA code introduce significant delay. I</DIV>
<DIV>can't find exact numbers regarding LMS tuning time, but IIRC it was</DIV>
<DIV>shorter than a GSM timeslot.</DIV>
<DIV> </DIV>
<DIV>So, as Sylvain said, given software limitations it's easier to use two</DIV>
<DIV>channels of UmTRX to receive on two frequencies.</DIV>
<DIV> </DIV>
<DIV>On Fri, Jun 7, 2013 at 11:21 AM, jiangwy <wyjiang@ljshuoda.com> wrote:</DIV>
<DIV>> Hi All,</DIV>
<DIV>></DIV>
<DIV>> I have a project to monitoring ( air sniffer ) the data between GSM BTS and</DIV>
<DIV>> MS using UmTRX.</DIV>
<DIV>> Uplink Transmission is delayed 3 slots than downlink from specification.</DIV>
<DIV>> So when I sync. with BTS and get the downlink slot data, I must switch the</DIV>
<DIV>> freqs of receiver from downlink to uplink in less than 2 slots.</DIV>
<DIV>> When the program call 'usrp_dev->set_rx_freq(wFreq)', How much time does the</DIV>
<DIV>> UmTRX switch to the 'wFreq' ?</DIV>
<DIV>></DIV>
<DIV>> Thanks in advance.</DIV>
<DIV>></DIV>
<DIV>> ________________________________</DIV>
<DIV>> Jiang WenYi</DIV>
<DIV> </DIV>
<DIV> </DIV>
<DIV> </DIV>
<DIV>-- </DIV>
<DIV>Regards,</DIV>
<DIV>Alexander Chemeris.</DIV>
<DIV>CEO, Fairwaves LLC / ООО УмРадио</DIV>
<DIV>http://fairwaves.ru</DIV></DIV></BODY></HTML>