Re: [Discuss-gnuradio] XCVR2450 simple questions
Hi, Now it is clear enough that the XCVR2450 is not full duplex. The question I asked in my first post in the case it is not full duplex is still unknown for me. How long does it take to the board to switch from transmission mode to reception mode? In the data sheet I can read a picture called "TX-RX turnaround frequency settling" but for me it is not very clear is the number I am looking for. Furthermore it scares me a little bit because if it takes several microseconds to change state will mean that is going to affect very seriously the minimum range of my radar detection system. It can take even the whole range (if I do not use an amplifier and a good antenna). Does anybody have any idea? Many thanks for your answers, Jorge >Well, then. > >Jason and I then were both confused. I thought it was full-duplex but >with the proviso that owing to it having only the one VFO/PLL, the >full-duplex had to be "same frequency", which would be perfect for >scenarios like radar. > >You have too many daughtercards, Matt :-) Makes it hard to keep track >of exactly which does what. > >-- >Marcus Leech >Principal Investigator >Shirleys Bay Radio Astronomy Consortium >http://www.sbrac.org >On 10/12/2010 07:33 PM, Matt Ettus wrote: >> >> >> NO. The XCVR2450 is NOT full duplex. I have never said anything >> different. The XCV2450 is NOT full duplex. Never was. Never will be. >> >> Matt >> >> ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
Re: [Discuss-gnuradio] XCVR2450 simple questions
On 10/12/2010 07:33 PM, Matt Ettus wrote: > > > NO. The XCVR2450 is NOT full duplex. I have never said anything > different. The XCV2450 is NOT full duplex. Never was. Never will be. > > Matt > > Well, then. Jason and I then were both confused. I thought it was full-duplex but with the proviso that owing to it having only the one VFO/PLL, the full-duplex had to be "same frequency", which would be perfect for scenarios like radar. You have too many daughtercards, Matt :-) Makes it hard to keep track of exactly which does what. -- Marcus Leech Principal Investigator Shirleys Bay Radio Astronomy Consortium http://www.sbrac.org ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
Re: [Discuss-gnuradio] XCVR2450 simple questions
On 10/12/2010 03:33 PM, Marcus D. Leech wrote: On 10/12/2010 06:05 PM, Jason Abele wrote: Ok, digging deeper into the max2829 datasheet, I stand corrected. The XCVR can not do full-duplex operation. My apologies for the confusion, our daughterboard app-notes will be updated shortly to reflect this correction. The RFX2400 is full-duplex capable in the 2.4GHz band. Jason It's true that table 5, page 28 doesn't show "TXENA" and "RXENA" both being "1" as a valid setting, but I wonder if it'll work anyway. If you look at the block diagram, it looks like same-frequency full-duplex might actually work. My recollection is that Matt posted about the XCVR2450 months ago, and indicated that it *would* do same-frequency full duplex. NO. The XCVR2450 is NOT full duplex. I have never said anything different. The XCV2450 is NOT full duplex. Never was. Never will be. Matt ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
Re: [Discuss-gnuradio] XCVR2450 simple questions
On 10/12/2010 06:05 PM, Jason Abele wrote: > Ok, digging deeper into the max2829 datasheet, I stand corrected. The > XCVR can not do full-duplex operation. My apologies for the > confusion, our daughterboard app-notes will be updated shortly to > reflect this correction. The RFX2400 is full-duplex capable in the > 2.4GHz band. > > Jason > > > It's true that table 5, page 28 doesn't show "TXENA" and "RXENA" both being "1" as a valid setting, but I wonder if it'll work anyway. If you look at the block diagram, it looks like same-frequency full-duplex might actually work. My recollection is that Matt posted about the XCVR2450 months ago, and indicated that it *would* do same-frequency full duplex. -- Marcus Leech Principal Investigator Shirleys Bay Radio Astronomy Consortium http://www.sbrac.org ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
Re: [Discuss-gnuradio] XCVR2450 simple questions
On Mon, Oct 11, 2010 at 11:05 AM, Jason Abele wrote: > On Mon, Oct 11, 2010 at 10:34 AM, Jorge Miguel wrote: >> My simple questions are: >> Does XCVR2450 work in full duplex mode? > > Yes, although with one synthesizer, it will be on the same frequency > for rx and tx > Ok, digging deeper into the max2829 datasheet, I stand corrected. The XCVR can not do full-duplex operation. My apologies for the confusion, our daughterboard app-notes will be updated shortly to reflect this correction. The RFX2400 is full-duplex capable in the 2.4GHz band. Jason ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
Re: [Discuss-gnuradio] XCVR2450 simple questions
On 10/11/2010 02:24 PM, Jorge Miguel wrote: > Jason, > > You are right my question about switching between tx and rx only makes > sense if it is no possible to tx and rx at the same time. > > Since you told me it is possible to it at the same frequency (that > means small doppler frequency shifts) the system looks promissing. I > was afraid of wasting most of the time of my unambiguous radar range > waiting to the system to switch to reception mode. > > Many thanks, > Jorge. Given that you can process several MHz of bandwidth around your center frequency, for doppler radar, the "same frequency" limitation would seem to not be a limitation at all. Unless your closing velocities are very very high :-) -- Principal Investigator Shirleys Bay Radio Astronomy Consortium http://www.sbrac.org ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
Re: [Discuss-gnuradio] XCVR2450 simple questions
Jason, You are right my question about switching between tx and rx only makes sense if it is no possible to tx and rx at the same time. Since you told me it is possible to it at the same frequency (that means small doppler frequency shifts) the system looks promissing. I was afraid of wasting most of the time of my unambiguous radar range waiting to the system to switch to reception mode. Many thanks, Jorge. On 11 October 2010 20:05, Jason Abele wrote: > On Mon, Oct 11, 2010 at 10:34 AM, Jorge Miguel wrote: > > My simple questions are: > > Does XCVR2450 work in full duplex mode? > > Yes, although with one synthesizer, it will be on the same frequency > for rx and tx > > > If yes: Does anybody know the isolation between tx and rx (Whole daughter > > board: transceiver,amplifier and RF switch) ? > > I do not have full characterization for you, but it will be dominated > by the antenna switch (U2), you can find the datasheet here: > > http://www.hw.com.tw/PDF/Switch/en/HWS383_v1.pdf > > Looks like ~30dB at 2.4GHz > > > If not: Does anybody know the time that XCVR2450 takes to switch from tx > to > > rx state ? > > It should be approximately the round-trip time for a control packet, > since you will not be tuning to a new frequency. However, because you > can do full-duplex, I doubt you need to switch. > > Jason > ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
Re: [Discuss-gnuradio] XCVR2450 simple questions
On 10/11/2010 01:34 PM, Jorge Miguel wrote: > Hi everybody! > > I read a lot of posts about XCVR2450 and I am still confused about its > performance. > I would like to set up a pulse doppler radar application around 2.4 > GHz with USRP2 + XCVR2450 > > My simple questions are: > Does XCVR2450 work in full duplex mode? > If yes: Does anybody know the isolation between tx and rx (Whole > daughter board: transceiver,amplifier and RF switch) ? > If not: Does anybody know the time that XCVR2450 takes to switch from > tx to rx state ? > > Many thanks in advance, > Jorge. > The XCVR2450 suports same-frequency full-duplex, which would be perfect for radar applications. It uses a MAX2829 802.11 world-band transceiver chip, which has only a single VFO in it, so the RX and TX sides have to be on the same frequency. The TX/RX isolation, based on reading the spec sheet for the switch, a HWS383, gives 29.5dB isolation for the 2.4Ghz range, and about 20.5dB isolation for the 5GHz side. I suspect that your application will be just fine on this card, using full-duplex, same-frequency mode. -- Marcus Leech Principal Investigator Shirleys Bay Radio Astronomy Consortium http://www.sbrac.org ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
Re: [Discuss-gnuradio] XCVR2450 simple questions
On Mon, Oct 11, 2010 at 10:34 AM, Jorge Miguel wrote: > My simple questions are: > Does XCVR2450 work in full duplex mode? Yes, although with one synthesizer, it will be on the same frequency for rx and tx > If yes: Does anybody know the isolation between tx and rx (Whole daughter > board: transceiver,amplifier and RF switch) ? I do not have full characterization for you, but it will be dominated by the antenna switch (U2), you can find the datasheet here: http://www.hw.com.tw/PDF/Switch/en/HWS383_v1.pdf Looks like ~30dB at 2.4GHz > If not: Does anybody know the time that XCVR2450 takes to switch from tx to > rx state ? It should be approximately the round-trip time for a control packet, since you will not be tuning to a new frequency. However, because you can do full-duplex, I doubt you need to switch. Jason ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
[Discuss-gnuradio] XCVR2450 simple questions
Hi everybody! I read a lot of posts about XCVR2450 and I am still confused about its performance. I would like to set up a pulse doppler radar application around 2.4 GHz with USRP2 + XCVR2450 My simple questions are: Does XCVR2450 work in full duplex mode? If yes: Does anybody know the isolation between tx and rx (Whole daughter board: transceiver,amplifier and RF switch) ? If not: Does anybody know the time that XCVR2450 takes to switch from tx to rx state ? Many thanks in advance, Jorge. ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
