Re: [USRP-users] Buffer underruns on x310 when transmitting and receiving from same channel cont.

2017-08-31 Thread Rob Kossler via USRP-users
Jason, I downloaded and compiled your program. Here are some remarks. - I accidentally ran your program using UHD 3.9.LTS. It worked fine! It even worked fine with Num Channels set to 2. I then realized my mistake and switched to 3.10. - I duplicated your results using UHD 3.10. Th

Re: [USRP-users] Performance Consistency of B200mini

2017-08-31 Thread Marcus D. Leech via USRP-users
On 08/31/2017 12:38 PM, Xingjian Chen wrote: I found it is about 1dB difference between measurements. Please check the attachment file for test results I captured by my b200mini. Do you know how to reduce this amplitude variation? What is the cause you think led to this issue? What version of

Re: [USRP-users] Initial phase offset at TX/ DC offset and LTE

2017-08-31 Thread Bakshi, Arjun via USRP-users
Correction: The thing I mentioned about all taps being phase shifted by the same amount isn't always observed. I tried it again with the same USRP, (and 2 USRPs with a MIMO) and I still get different channels every time I start the flow graph. Identifying multiple taps: the channel estimate I

[USRP-users] How to Access a user register in fpga of X310 using UHD (3.10.2)

2017-08-31 Thread Karan Suri via USRP-users
Hello Users I recently stumbled onto a problem. I need to implement a gain control mechanism by left shifting bits of the received data, when the rx power is considerably low. I need to define a settings register which controls the shift amount, but I need to get access to this setting register us

[USRP-users] Rotating constellations and varying LOs with USRP B210 + Board Mounted GPSDO

2017-08-31 Thread George Sklivanitis via USRP-users
Hi everyone, Has anyone noticed unstable LOs or carrier frequency offsets when using USRP B210s with board mounted GPSDOs? We have recently been doing field tests using GPS-disciplined oscillators for both USRP B210s and USRP N210 and occasionally both transmitter and receiver flowgraphs lose GPS

Re: [USRP-users] Rotating constellations and varying LOs with USRP B210 + Board Mounted GPSDO

2017-08-31 Thread Marcus D. Leech via USRP-users
On 08/31/2017 10:08 PM, George Sklivanitis via USRP-users wrote: Hi everyone, Has anyone noticed unstable LOs or carrier frequency offsets when using USRP B210s with board mounted GPSDOs? We have recently been doing field tests using GPS-disciplined oscillators for both USRP B210s and USRP N

Re: [USRP-users] Distance estimation and phase continuity of LO

2017-08-31 Thread Kyeong Su Shin via USRP-users
Hello All, Just want to note that NI 2921s use XCVR2450, which is half-duplex (cannot rx and tx concurrently). B210s will work better, as they are full-duplex 2x2 MIMO. Regards, Kyeong Su Shin On Wed, Aug 30, 2017 at 8:44 PM, Michael Don via USRP-users < usrp-users@lists.ettus.com> wrote: > > U