# GNU Radio **URL:** https://www.ruby-forum.com/c/gnu-radio/15.md?page=86 [Latest](https://www.ruby-forum.com/latest.md) · [Categories](https://www.ruby-forum.com/categories.md) · [Tags](https://www.ruby-forum.com/tags.md) **Page:** 87 --- ## [Gr-cdma is ready](https://www.ruby-forum.com/t/gr-cdma-is-ready/239618)
**Author:** [@musicdenotation](https://www.ruby-forum.com/u/musicdenotation)\ **Replies:** 1\ **Last updated:** [March 8, 2014, 12:51pm UTC](https://www.ruby-forum.com/t/gr-cdma-is-ready/239618 "2014-03-08T12:51:47Z")
Dear all, the OOT module gr-cdma that we have been working on with Zhe F. is now ready (also fully documented). You can find it here: An important acknowledgement: this project grew out of the DARPA SPECTRUM CHALLE… --- ## [Need help to understand code of sync:decimator block](https://www.ruby-forum.com/t/need-help-to-understand-code-of-sync-decimator-block/239639)
**Author:** [@musicdenotation](https://www.ruby-forum.com/u/musicdenotation)\ **Replies:** 5\ **Last updated:** [March 8, 2014, 12:26pm UTC](https://www.ruby-forum.com/t/need-help-to-understand-code-of-sync-decimator-block/239639 "2014-03-08T12:26:17Z")
Hello, I am using GNU Radio version 3.6.5 and trying to write a block to calculate average of 5 samples. I want to produce one average output corresponding to 5 input samples. I am using set\_history(5) to remember p… --- ## [Creating OOT module](https://www.ruby-forum.com/t/creating-oot-module/239588)
**Author:** [@Detlef\_R](https://www.ruby-forum.com/u/Detlef_R)\ **Replies:** 3\ **Last updated:** [March 8, 2014, 8:47am UTC](https://www.ruby-forum.com/t/creating-oot-module/239588 "2014-03-08T08:47:15Z")
Hello everyone! Met a problem, cannot create OOT module. Red manuals, wiki, howto… In wiki says, that gr\_modtool is included in distribut of GNURadio, but I have not found it there. I download it from ftp, but, again,… --- ## [Graph plotting using wxPython](https://www.ruby-forum.com/t/graph-plotting-using-wxpython/239638)
**Author:** [@Detlef\_R](https://www.ruby-forum.com/u/Detlef_R)\ **Replies:** 0\ **Last updated:** [March 8, 2014, 7:37am UTC](https://www.ruby-forum.com/t/graph-plotting-using-wxpython/239638 "2014-03-08T07:37:31Z")
Dear Sir, I am trying to build a custom block to plot graphs. For starting this block is similar to the block of “WX GUI Scope Sink”. I started with wxPython, the code is below. The problem is, this block causes the… --- ## [The GMSK demodulation](https://www.ruby-forum.com/t/the-gmsk-demodulation/239482)
**Author:** [@musicdenotation](https://www.ruby-forum.com/u/musicdenotation)\ **Replies:** 20\ **Last updated:** [March 8, 2014, 5:50am UTC](https://www.ruby-forum.com/t/the-gmsk-demodulation/239482 "2014-03-08T05:50:39Z")
Hi, As I have known, GSM uses GMSK modulation which BT = 0.3 and it uses Viterbi algorithm for demodulation. And I took a look at the code of GMSK demod code in GNU Radio, it use quadrature\_demod but not Viterbi as … --- ## [Frequency response from fading simulator block not working as expected](https://www.ruby-forum.com/t/frequency-response-from-fading-simulator-block-not-working-as-expected/239480)
**Author:** [@musicdenotation](https://www.ruby-forum.com/u/musicdenotation)\ **Replies:** 2\ **Last updated:** [March 7, 2014, 8:05pm UTC](https://www.ruby-forum.com/t/frequency-response-from-fading-simulator-block-not-working-as-expected/239480 "2014-03-07T20:05:49Z")
Hello, In order to simulate a multi-path scenario, Im trying to validate the “Frequency Selective Fading Model” block, but the results I found are not the ones I would expect. The set up consisted of 2 taps delayed … --- ## [Rayleigh fading simulator](https://www.ruby-forum.com/t/rayleigh-fading-simulator/239499)
**Author:** [@musicdenotation](https://www.ruby-forum.com/u/musicdenotation)\ **Replies:** 4\ **Last updated:** [March 7, 2014, 12:13pm UTC](https://www.ruby-forum.com/t/rayleigh-fading-simulator/239499 "2014-03-07T12:13:06Z")
Helo all, I need your help for simulation of the Rayleigh fading. I know that I can use GNURADIO channel models, but I need to know how they simulated. For example I am looking into the ‘fading\_model\_impl.cc’ in chan… --- ## [GSoC14 MIMO Transeiver](https://www.ruby-forum.com/t/gsoc14-mimo-transeiver/239621)
**Author:** [@musicdenotation](https://www.ruby-forum.com/u/musicdenotation)\ **Replies:** 0\ **Last updated:** [March 7, 2014, 8:30am UTC](https://www.ruby-forum.com/t/gsoc14-mimo-transeiver/239621 "2014-03-07T08:30:32Z")
Hello, We are students of IIIT-Hyderbad, India, doing MS By Research and are interested in participating GSoC-14 by building GRC gr-MIMO module. We are from communication background and have fundamental knowledge of … --- ## [Gr\_modtool](https://www.ruby-forum.com/t/gr-modtool/239591)
**Author:** [@Detlef\_R](https://www.ruby-forum.com/u/Detlef_R)\ **Replies:** 2\ **Last updated:** [March 7, 2014, 2:14am UTC](https://www.ruby-forum.com/t/gr-modtool/239591 "2014-03-07T02:14:44Z")
hi i use gr\_modtool to add a new block in an exist module,it apper this : No GNU Radio module found in the given directory. Quitting. what shoud i do to solve it thanks, BZS --- ## [RTLSDR dongle posting](https://www.ruby-forum.com/t/rtlsdr-dongle-posting/239603)
**Author:** [@musicdenotation](https://www.ruby-forum.com/u/musicdenotation)\ **Replies:** 2\ **Last updated:** [March 6, 2014, 10:39pm UTC](https://www.ruby-forum.com/t/rtlsdr-dongle-posting/239603 "2014-03-06T22:39:56Z")
Hi, The reason I signed up was that I saw a post (Google) on GNU Radio regarding the RTLSDR dongles to which I wanted to respond. How do I attach a post to a thread from the recent past for which I do not have the … --- ## [GSOC 2014 possible project proposal( plain text mode)](https://www.ruby-forum.com/t/gsoc-2014-possible-project-proposal-plain-text-mode/239613)
**Author:** [@musicdenotation](https://www.ruby-forum.com/u/musicdenotation)\ **Replies:** 0\ **Last updated:** [March 6, 2014, 7:43pm UTC](https://www.ruby-forum.com/t/gsoc-2014-possible-project-proposal-plain-text-mode/239613 "2014-03-06T19:43:45Z")
My apologies, first email was send with some HTML content. Hello: My name is Damian Miralles, I am a senior computer engineering students at the Polytechnic University of Puerto Rico. I am very interested inparticipa… --- ## [GSOC 2014 possible project proposal](https://www.ruby-forum.com/t/gsoc-2014-possible-project-proposal/239612)
**Author:** [@musicdenotation](https://www.ruby-forum.com/u/musicdenotation)\ **Replies:** 0\ **Last updated:** [March 6, 2014, 7:24pm UTC](https://www.ruby-forum.com/t/gsoc-2014-possible-project-proposal/239612 "2014-03-06T19:24:16Z")
Hello: My name is Damian Miralles, I am a senior computer engineering students at the Polytechnic University of Puerto Rico. I am very interested inparticipating into the GSOC 2014 program and saw some of the ideas … --- ## [Error in "Constellation Decoder" block](https://www.ruby-forum.com/t/error-in-constellation-decoder-block/239563)
**Author:** [@Detlef\_R](https://www.ruby-forum.com/u/Detlef_R)\ **Replies:** 6\ **Last updated:** [March 6, 2014, 7:04pm UTC](https://www.ruby-forum.com/t/error-in-constellation-decoder-block/239563 "2014-03-06T19:04:13Z")
Hi All, I am manipulating GNU Radio Companion. While using the “Constellation Decoder” block, I have put digital.constellation\_qpsk as a “Constellation Object” argument. But, I have found an error when I have execut… --- ## [Noisy APT images](https://www.ruby-forum.com/t/noisy-apt-images/239607)
**Author:** [@musicdenotation](https://www.ruby-forum.com/u/musicdenotation)\ **Replies:** 1\ **Last updated:** [March 6, 2014, 6:22pm UTC](https://www.ruby-forum.com/t/noisy-apt-images/239607 "2014-03-06T18:22:19Z")
Hi, I’m trying to receive APT images from NOAA with a QHA antenna and I received noisy images. I use a usrp source block, then a low pass filter with 50 kHz of cutoff and 20 kHz of transition width, then a WBFM recei… --- ## [Gr\_buffer::allocate\_buffer: warning and USRP tx underflow](https://www.ruby-forum.com/t/gr-buffer-warning-and-usrp-tx-underflow/239598)
**Author:** [@musicdenotation](https://www.ruby-forum.com/u/musicdenotation)\ **Replies:** 1\ **Last updated:** [March 6, 2014, 4:53pm UTC](https://www.ruby-forum.com/t/gr-buffer-warning-and-usrp-tx-underflow/239598 "2014-03-06T16:53:01Z")
Hi, My gnuradio flow graph has a custom block taking input from multiple USRP’s and the output of the block is connected to a USRP transmitter. My applications demands a sample rate of at least 5Msps and up to 10Msp… --- ## [GSoC gr-gsm OOT module](https://www.ruby-forum.com/t/gsoc-gr-gsm-oot-module/239360)
**Author:** [@musicdenotation](https://www.ruby-forum.com/u/musicdenotation)\ **Replies:** 2\ **Last updated:** [March 6, 2014, 4:51pm UTC](https://www.ruby-forum.com/t/gsoc-gr-gsm-oot-module/239360 "2014-03-06T16:51:12Z")
I am currently working on a proof of concept system, and for which, I am using a patched version of airprobe, for GSM reception, using GNURadio. I want to contribute along side to the mainline and would like to know … --- ## [Problem with undefined symbol in new block created by gr\_modtool in 3.7.2](https://www.ruby-forum.com/t/problem-with-undefined-symbol-in-new-block-created-by-gr-modtool-in-3-7-2/239587)
**Author:** [@Detlef\_R](https://www.ruby-forum.com/u/Detlef_R)\ **Replies:** 6\ **Last updated:** [March 6, 2014, 10:56am UTC](https://www.ruby-forum.com/t/problem-with-undefined-symbol-in-new-block-created-by-gr-modtool-in-3-7-2/239587 "2014-03-06T10:56:54Z")
Hello all, I am dealing with the problem of undefined symbol when trying to execute a python script for testing my new custom block created in GNU Radio 3.7.2. I used gr\_modtool for creating the new block and also f… --- ## [Data extract from file sink block](https://www.ruby-forum.com/t/data-extract-from-file-sink-block/239597)
**Author:** [@Detlef\_R](https://www.ruby-forum.com/u/Detlef_R)\ **Replies:** 1\ **Last updated:** [March 6, 2014, 10:22am UTC](https://www.ruby-forum.com/t/data-extract-from-file-sink-block/239597 "2014-03-06T10:22:16Z")
Hi all, How to use file sink block in GRC. I want to extract output data from rx\_ofdm & tx\_ofdm examples bolck in GNU radio to plot BER V/s EB/N0 in MATLAB. If I use file sink blocks, it’s generate a banary file which… --- ## [\[VOLK\] Working Group reminder and invitation](https://www.ruby-forum.com/t/volk-working-group-reminder-and-invitation/239562)
**Author:** [@musicdenotation](https://www.ruby-forum.com/u/musicdenotation)\ **Replies:** 1\ **Last updated:** [March 6, 2014, 12:49am UTC](https://www.ruby-forum.com/t/volk-working-group-reminder-and-invitation/239562 "2014-03-06T00:49:24Z")
All, Based on the G+ responses there should be a pretty good turn out for the VOLK working group call tomorrow. This is partially a reminder (in case those G+ reminders aren’t enough) and an invitation for GSoC stude… --- ## [Gr-audio OSX fixes test branch](https://www.ruby-forum.com/t/gr-audio-osx-fixes-test-branch/239321)
**Author:** [@Detlef\_R](https://www.ruby-forum.com/u/Detlef_R)\ **Replies:** 10\ **Last updated:** [March 5, 2014, 11:10pm UTC](https://www.ruby-forum.com/t/gr-audio-osx-fixes-test-branch/239321 "2014-03-05T23:10:08Z")
I just pushed the latest WIP for fixing gr-audio on OSX; I hope some adventurous OSX users can test this branch out & provide feedback! If you want to help, but don’t know how, ask me and I’ll provide instructions. -… --- ## [Summit on SDR](https://www.ruby-forum.com/t/summit-on-sdr/239434)
**Author:** [@Detlef\_R](https://www.ruby-forum.com/u/Detlef_R)\ **Replies:** 2\ **Last updated:** [March 5, 2014, 9:08pm UTC](https://www.ruby-forum.com/t/summit-on-sdr/239434 "2014-03-05T21:08:03Z")
Dear Group, We are doing a multi-disciplinary faculty summit in Gr. Noida on 8th March’14. Wireless communication is also one of the parallel tracks. Sole purpose of the summit is to create awareness about SDR and re… --- ## [GSOC 14 project "Vector Network Analyzer"](https://www.ruby-forum.com/t/gsoc-14-project-vector-network-analyzer/239557)
**Author:** [@musicdenotation](https://www.ruby-forum.com/u/musicdenotation)\ **Replies:** 5\ **Last updated:** [March 5, 2014, 6:08pm UTC](https://www.ruby-forum.com/t/gsoc-14-project-vector-network-analyzer/239557 "2014-03-05T18:08:32Z")
Hi I am Mitul Vekariya https://github.com/mitul93 - final year student of Electronics and Communication (ECE) branch at Nirma University, India. I am very interested in mentioned projecthttp://gnuradio.org/redmine/pr… --- ## [GSoC - Integration of GNU Radio into Eclipse](https://www.ruby-forum.com/t/gsoc-integration-of-gnu-radio-into-eclipse/239580)
**Author:** [@Detlef\_R](https://www.ruby-forum.com/u/Detlef_R)\ **Replies:** 1\ **Last updated:** [March 5, 2014, 6:06pm UTC](https://www.ruby-forum.com/t/gsoc-integration-of-gnu-radio-into-eclipse/239580 "2014-03-05T18:06:08Z")
Hi everybody! My name is Kirill Snezhko and i am a student of Bauman Moscow State Technical University and an exchange student in Hochschule Bonn-Rhein-Sieg. I am very interested in this topic - Integration of GNU Ra… --- ## [SDR FM Transmitters](https://www.ruby-forum.com/t/sdr-fm-transmitters/239579)
**Author:** [@musicdenotation](https://www.ruby-forum.com/u/musicdenotation)\ **Replies:** 0\ **Last updated:** [March 5, 2014, 4:43pm UTC](https://www.ruby-forum.com/t/sdr-fm-transmitters/239579 "2014-03-05T16:43:32Z")
Hi, recently, there’s lot’s of low power FM transmitters on eBay. Looks like there was some change in the US allowing low power stations… Anyways, I now stumbled over an SDR version (http://www.ebay.com/itm/261391237… --- ## [Not understanding the HRPT receiver](https://www.ruby-forum.com/t/not-understanding-the-hrpt-receiver/239578)
**Author:** [@musicdenotation](https://www.ruby-forum.com/u/musicdenotation)\ **Replies:** 0\ **Last updated:** [March 5, 2014, 4:30pm UTC](https://www.ruby-forum.com/t/not-understanding-the-hrpt-receiver/239578 "2014-03-05T16:30:00Z")
Hi, I downloaded the usrp\_rx\_hrpt receiver from gr-noaa repository and I don’t understand the scheme. If someone could help me I would really appreciate it. Regards, Pablo. --- ## [How to write a block](https://www.ruby-forum.com/t/how-to-write-a-block/239566)
**Author:** [@musicdenotation](https://www.ruby-forum.com/u/musicdenotation)\ **Replies:** 1\ **Last updated:** [March 5, 2014, 10:22am UTC](https://www.ruby-forum.com/t/how-to-write-a-block/239566 "2014-03-05T10:22:08Z")
hi, how to use the gr\_modtoolto write a block inherent from a in\_tree\_block,such as inherent from stream\_to \_vector BZS --- ## [(GSoC) MIMO system](https://www.ruby-forum.com/t/gsoc-mimo-system/239367)
**Author:** [@Detlef\_R](https://www.ruby-forum.com/u/Detlef_R)\ **Replies:** 9\ **Last updated:** [March 4, 2014, 5:34pm UTC](https://www.ruby-forum.com/t/gsoc-mimo-system/239367 "2014-03-04T17:34:29Z")
Hello everyone, I’m a graduate student from China. I major in Computer Science and my research focus on wireless networks. Today, I’m glad to share some of my ideas on MIMO with you. (maybe a little pleonastic) Defin… --- ## [IEEE DySPAN conference](https://www.ruby-forum.com/t/ieee-dyspan-conference/239552)
**Author:** [@Detlef\_R](https://www.ruby-forum.com/u/Detlef_R)\ **Replies:** 0\ **Last updated:** [March 4, 2014, 4:13pm UTC](https://www.ruby-forum.com/t/ieee-dyspan-conference/239552 "2014-03-04T16:13:53Z")
I try not to use this list to promote many conferences, but DySPAN is one that I go to (almost) every year and is very relevant to our project. There are definitely many GNU Radio users that go, but I wouldn’t mind se… --- ## [FFTW3 runtime error](https://www.ruby-forum.com/t/fftw3-runtime-error/239541)
**Author:** [@musicdenotation](https://www.ruby-forum.com/u/musicdenotation)\ **Replies:** 4\ **Last updated:** [March 4, 2014, 2:59pm UTC](https://www.ruby-forum.com/t/fftw3-runtime-error/239541 "2014-03-04T14:59:40Z")
Dear Sir, I am trying to build a custom block with FFT capability. I use FFTW3, the FFT stuff runs well as a standalone program before integrating into gnuradio. Then I integrate the FFT function into the block, it c… --- ## [Using both antennas of USRP as Receivers](https://www.ruby-forum.com/t/using-both-antennas-of-usrp-as-receivers/239544)
**Author:** [@Detlef\_R](https://www.ruby-forum.com/u/Detlef_R)\ **Replies:** 1\ **Last updated:** [March 4, 2014, 1:36pm UTC](https://www.ruby-forum.com/t/using-both-antennas-of-usrp-as-receivers/239544 "2014-03-04T13:36:38Z")
Is it possible to use both the antennas of USRP as receive antennas? For example TX/RX should work on frequency f1 as a receive antenna and RX2 should work on frequency f2 as another receive antenna. Also, USRP should … [Previous page](https://www.ruby-forum.com/c/gnu-radio/15.md?page=85) [Next page](https://www.ruby-forum.com/c/gnu-radio/15.md?page=87)