Hello all, Lately, I am experimenting with an implementation of a point-to-point On-off Keying communication system. I mostly prefer to use the USRP as the receiver, in which I can capture samples and later process them through Matlab. However, because of the algorithms I try to apply at the receiver (packet/symbol synchronization, channel estimation, carrier-frequency offset cancellation, detection) I have to deal with a lot of delay at the receiver processing part. As a result, my transmitter keeps sending packets which will either get lost or stored at the fifo. Therefore, I would like to know, if it is possible to construct a second buffer (softwarely in Matlab) in order not to lose so many data packets. Does anyone have an intuition about the way the fifo is used? Thanks, GS -- Sklivanitis Georgios M.Sc. Student Telecommunications Division, Department of Electronics and Computer Engineering Technical University of Crete, Kounoupidiana Campus, Office 145.A10 Chania, Crete, 73100, Greece Tel. : 28210 59257 www.telecom.tuc.gr/~gsklivanitis

Hello all, Lately, I am experimenting with a point-to-point SDR link where my transmitter uses On-Off Keying modulation while the receiver follows techniques for efficient signal processing and detection (non-coherent, coherent). My major problem is how can I measure the input SNR as a ratio of the power of the received signal to the power of noise, given also that we ignore the quantity of NF (Noise Figure). Thank you in advance for your concern, GS -- Sklivanitis Georgios M.Sc. Student Telecommunications Division, Department of Electronics and Computer Engineering Technical University of Crete, Kounoupidiana Campus, Office 145.A10 Chania, Crete, 73100, Greece Tel. : 28210 59257 www.telecom.tuc.gr/~gsklivanitis

One method would be to use a single pole IIR filter to get an average of the noise floor energy, and compare that with the average symbol energy. On Wed, Jul 6, 2011 at 6:49 AM, George Sklivanitis < george.sklivanitis@gmail.com> wrote: > Hello all, > > Lately, I am experimenting with a point-to-point SDR link where my > transmitter uses On-Off Keying modulation while the receiver follows > techniques for efficient signal processing and detection (non-coherent, > coherent). My major problem is how can I measure the input SNR as a ratio of > the power of the received signal to the power of noise, given also that we > ignore the quantity of NF (Noise Figure). > > Thank you in advance for your concern, > > GS > > > -- > Sklivanitis Georgios > M.Sc. Student > Telecommunications Division, > Department of Electronics and Computer Engineering > Technical University of Crete, > Kounoupidiana Campus, Office 145.A10 > Chania, Crete, 73100, Greece > Tel. : 28210 59257 > www.telecom.tuc.gr/~**gsklivanitis<http://www.telecom.tuc.gr/~gsklivanitis> > > > ______________________________**_________________ > USRP-users mailing list > USRP-users@lists.ettus.com > http://lists.ettus.com/**mailman/listinfo/usrp-users_**lists.ettus.com<http://lists.ettus.com/mailman/listinfo/usrp-users_lists.ettus.com> >

 Hello all,

 Lately, I am experimenting with a point-to-point SDR link where my
 transmitter uses On-Off Keying modulation while the receiver
 follows techniques for efficient signal processing and detection
 (non-coherent, coherent). My major problem is how can I measure
 the input SNR as a ratio of the power of the received signal to
 the power of noise, given also that we ignore the quantity of NF
 (Noise Figure).

 Thank you in advance for your concern,

 GS


 -- 
 Sklivanitis Georgios
 M.Sc. Student
 Telecommunications Division,
 Department of Electronics and Computer Engineering
 Technical University of Crete,
 Kounoupidiana Campus, Office 145.A10
 Chania, Crete, 73100, Greece
 Tel. : 28210 59257
 www.telecom.tuc.gr/~gsklivanitis
 <http://www.telecom.tuc.gr/%7Egsklivanitis>


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On 7/6/11 8:20 PM, Colby Boyer wrote: > One method would be to use a single pole IIR filter to get an average > of the noise floor energy, and compare that with the average symbol > energy. > > On Wed, Jul 6, 2011 at 6:49 AM, George Sklivanitis > <george.sklivanitis@gmail.com <mailto:george.sklivanitis@gmail.com>> > wrote: > > Hello all, > > Lately, I am experimenting with a point-to-point SDR link where my > transmitter uses On-Off Keying modulation while the receiver > follows techniques for efficient signal processing and detection > (non-coherent, coherent). My major problem is how can I measure > the input SNR as a ratio of the power of the received signal to > the power of noise, given also that we ignore the quantity of NF > (Noise Figure). > > Thank you in advance for your concern, > > GS > > > -- > Sklivanitis Georgios > M.Sc. Student > Telecommunications Division, > Department of Electronics and Computer Engineering > Technical University of Crete, > Kounoupidiana Campus, Office 145.A10 > Chania, Crete, 73100, Greece > Tel. : 28210 59257 > www.telecom.tuc.gr/~gsklivanitis > <http://www.telecom.tuc.gr/%7Egsklivanitis> > > > _______________________________________________ > USRP-users mailing list > USRP-users@lists.ettus.com <mailto:USRP-users@lists.ettus.com> > http://lists.ettus.com/mailman/listinfo/usrp-users_lists.ettus.com > > Hello again, Could it be sufficient enough to say that we measure the noise's variance as the variance of the data captured when nobody transmits in the desired frequency and then the ratio of the received signal energy to the noise's energy plus 1 will give us the estimated Signal-to-Noise ratio? Thanks, GS -- Sklivanitis Georgios M.Sc. Student Telecommunications Division, Department of Electronics and Computer Engineering Technical University of Crete, Kounoupidiana Campus, Office 145.A10 Chania, Crete, 73100, Greece Tel. : 28210 59257 www.telecom.tuc.gr/~gsklivanitis

It'll probably ball park the figure. You can then cross-validate it with the error rate. On Wed, Jul 6, 2011 at 11:50 AM, George Sklivanitis < george.sklivanitis@gmail.com> wrote: > ** > On 7/6/11 8:20 PM, Colby Boyer wrote: > > One method would be to use a single pole IIR filter to get an average of > the noise floor energy, and compare that with the average symbol energy. > > On Wed, Jul 6, 2011 at 6:49 AM, George Sklivanitis < > george.sklivanitis@gmail.com> wrote: > >> Hello all, >> >> Lately, I am experimenting with a point-to-point SDR link where my >> transmitter uses On-Off Keying modulation while the receiver follows >> techniques for efficient signal processing and detection (non-coherent, >> coherent). My major problem is how can I measure the input SNR as a ratio of >> the power of the received signal to the power of noise, given also that we >> ignore the quantity of NF (Noise Figure). >> >> Thank you in advance for your concern, >> >> GS >> >> >> -- >> Sklivanitis Georgios >> M.Sc. Student >> Telecommunications Division, >> Department of Electronics and Computer Engineering >> Technical University of Crete, >> Kounoupidiana Campus, Office 145.A10 >> Chania, Crete, 73100, Greece >> Tel. : 28210 59257 >> www.telecom.tuc.gr/~gsklivanitis<http://www.telecom.tuc.gr/%7Egsklivanitis> >> >> >> _______________________________________________ >> USRP-users mailing list >> USRP-users@lists.ettus.com >> http://lists.ettus.com/mailman/listinfo/usrp-users_lists.ettus.com >> > > Hello again, > > Could it be sufficient enough to say that we measure the noise's variance > as the variance of the data captured when nobody transmits in the desired > frequency and then the ratio of the received signal energy to the noise's > energy plus 1 will give us the estimated Signal-to-Noise ratio? > > Thanks, > GS > > -- > Sklivanitis Georgios > M.Sc. Student > Telecommunications Division, > Department of Electronics and Computer Engineering > Technical University of Crete, > Kounoupidiana Campus, Office 145.A10 > Chania, Crete, 73100, Greece > Tel. : 28210 59257www.telecom.tuc.gr/~gsklivanitis > >