Hi Oliver You could add a multiplexer so that you can choose to bypass the finedelay_fstop_prog block when you don't want that functionality.
Regards Andrew On Mon, Feb 23, 2015 at 2:36 PM, Wang Jinqing <[email protected]> wrote: > Hi, > > Thank you very much. I know how the parameters now. But it seems hard to > set the phase(channel_index) zero. Because some time I also want to use > the two channel correlator to deal with one antenna's RCP and LCP cross > correlation. At this situation I should set the phase(channel_index) > zero. Do you know how to set the core's output phase(channel_index) zero? > > Best Regards. > > Oliver Wang > > -----原始邮件----- > *发件人:* "Andrew Martens" <[email protected]> > *发送时间:* 2015年2月20日 星期五 > *收件人:* "Wang Jinqing" <[email protected]> > *抄送:* "[email protected]" <[email protected]> > *主题:* Re: Re: [casper] question about finedelay_fstop_prog > > > Hi > > From what I can see of the block internals; > > The phase slope generated is in the form > phase(channel_index) = slope*channel_index + offset > > slope = theta_fract > offset = theta_fs + samples/fft_fs > > So setting theta_fract to 0 and theta_fs starts the phase at 0 but the > phase will slowly increase (see Fringe_Theat_Cnt1). > > Regards > Andrew > > On Fri, Feb 20, 2015 at 3:48 PM, Wang Jinqing <[email protected]> wrote: > >> Hi, thank you >> >> But I have set the theta_fract zero,this means that the phase changing >> every 4095 FFT cycles is zero, So the output phase should be stable. But >> now is not like that. >> >> Best Regards. >> >> Oliver Wang >> >> >> -----原始邮件----- >> *发件人:* "Andrew Martens" <[email protected]> >> *发送时间:* 2015年2月20日 星期五 >> *收件人:* "Wang Jinqing" <[email protected]> >> *抄送:* "[email protected]" <[email protected]> >> *主题:* Re: [casper] question about finedelay_fstop_prog >> >> >> Hi Oliver >> >> From what I can see, that port determines how quickly the phase offset >> applied to all channels is incremented. So your value tells it to increment >> the phase offset every 4095 cycles. I am not sure if there is some way to >> turn off fringe-stopping. >> >> There is some good documentation at >> https://casper.berkeley.edu/wiki/Finedelay_fstop_prog which may help. >> >> Regards >> Andrew >> >> On Fri, Feb 20, 2015 at 3:06 PM, Wang Jinqing <[email protected]> wrote: >> >>> Hi, >>> >>> I want to use the core finedelay_fstop_prog to design a FX >>> correlator( two stations ) after FFT as the appendix. I have set >>> theta_fract and theta_fs all zeros, fft_fs 4095. I think in this design the >>> the correlated phase should be constant with time. But when I input a >>> sine wave signal then devides into two channels( as two stations' >>> signal), the correlated phase is changing with time. I have tested the >>> model after I removed the finedelay_fstop_prog core and I found >>> the correlated phase is stable. So I think I may set the >>> finedelay_fstop_prog's input parameters not correct. But how to set the >>> parameters correctlly? >>> >>> Best Regards. >>> >>> Oliver Wang >>> >>> >>> >>> >> >> >> >> >> > > > > >
