[Discuss-gnuradio] calc_metric in digital_constellation_receiver
I want to use trellis codes along with generic_mod_demod. 1. Can I replace the constellation_receiver object with a trellis_metric followed by a viterbi? If so is it required to have an operation equivalent to phase correction in constellation_receiver? How can I do that? 2. There is a function for metric calculation inside constellation_receiver. Can I use it to implement viterbi? Thanks in advance -- Manu T S ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org https://lists.gnu.org/mailman/listinfo/discuss-gnuradio
[Discuss-gnuradio] OP25 error- ioctl(d_tap, TUNSETIFF, &ifr): Operation not permitted
I know none of you are working on OP25 but has anyone seen this error? i cant find anything on the web about this. I already had to disable the Waterfall sink and the FFT sink in order to get rid of the "AttributeError: 'gr_hier_block2_sptr' object has no attribute 'set_callback'" error. Now OP25 dies this way: Imported legacy fsk4 Using Volk machine: ssse3_32 RTL2832 Source block configuration: Read length (bytes): 262144 Buffer enabled: yes Buffer multiplier: 8 Buffer size (samples): 1048576 Samples per read: 131072 Buffer level: 50.0% Successfully initialised demod: "ezcap EzTV" Probing "e4k"...not found. Probing "fc0013"...not found. Probing "fc2580"...bad check value. Probing "fc0012"...not found. Probing "e4000"...not found. Could not find tuner automatically after probe Found RTL2832 device: ezcap EzTV (tuner: interface not implemented) Sample rate range: 91 - 320 Hz Crystal frequency: 2880 Hz Wait delay: 196.608 ms ioctl(d_tap, TUNSETIFF, &ifr): Operation not permitted Using legacy decoder_ff I'm using Unbuntu 12.10, GNUradio 3.6.3, python 2.7.3, and NooElec R820T RTL2832 stick. I installed GNUradio using the build script on Balint's "how to build page" but OP25 I had to build from source because the build script there has a broken link. Any help will be much appreciated. ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org https://lists.gnu.org/mailman/listinfo/discuss-gnuradio
[Discuss-gnuradio] Receiving My Own Transmitted Packets after disconnecting from Transmit Path and connecting to Receive Path
Hi,
I wrote a gnuRadio code that allows me to switch between a Tx_Path and
Rx_Path every 10 seconds.
The code is based on the tb.lock() , tb.unlock() functions and the
benchmarks provided with gnuradio.
I am able to do the switching fine, however after switching from
transmission to reception, the node receives some of the packets that were
sent during its own transmission period.
How can I overcome this echo like effect between the TX and RX periods ?
*
*
*In the main() function I have :
*
tb.start()
while True:
time.sleep(10)
tb.lock()
tb.conf_transmit()
tb.unlock()
tb.transmit_packets()
tb.lock()
tb.conf_sense()
tb.unlock()
tb.wait()
*In the top_block class I have:*
def conf_transmit(self):
self.disconnect(self.source, self.rxpath)
self.connect(self.txpath, self.sink)
def conf_sense(self):
self.disconnect(self.txpath, self.sink)
self.connect(self.source, self.rxpath)
def transmit_packets(self):
begin_time = time.time()
pkt_size=1500
pktno = 0
while time.time() - begin_time < 10: # Send for 10 minutes
data = (pkt_size - 2) * chr(pktno & 0xff)
payload = struct.pack('!H', pktno & 0x) + data
self.send_pkt(payload)
pktno += 1
def send_pkt(self, payload='', eof=False):
### Main Function to Send Packets.
return self.txpath.send_pkt(payload, eof)
Best Regards,
--
Yahya Ezzeldin
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Re: [Discuss-gnuradio] calc_metric in digital_constellation_receiver
On Sun, Feb 24, 2013 at 6:36 AM, Manu T S wrote: > I want to use trellis codes along with generic_mod_demod. > > 1. Can I replace the constellation_receiver object with a trellis_metric > followed by a viterbi? If so is it required to have an operation equivalent > to phase correction in constellation_receiver? How can I do that? constellation_receiver has four optional outputs. The fourth is a phase-corrected complex number. You could use this as the input to your metric calculation. > > 2. There is a function for metric calculation inside constellation_receiver. > Can I use it to implement viterbi? This function is called by trellis.constellation_metrics_cf which generates metrics that you can feed into the viterbi block. Metrics are calculated for every constellation point, so for large constellations the efficiency will be appalling. > > Thanks in advance > > > -- > Manu T S > > ___ > Discuss-gnuradio mailing list > Discuss-gnuradio@gnu.org > https://lists.gnu.org/mailman/listinfo/discuss-gnuradio > ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org https://lists.gnu.org/mailman/listinfo/discuss-gnuradio
Re: [Discuss-gnuradio] What is IF data header?
On 02/23/2013 12:56 AM, Gong Zhang wrote: > Hi, >I found the following notes in file metadata.hpp in UHD: >/*! > * RX metadata structure for describing sent IF data. > * Includes time specification, fragmentation flags, burst flags, and > error codes. > * The receive routines will convert IF data headers into metadata. > */ >Are the IF data header ethernet packet header?Or anything else? >Thanks. > Its referring to an VITA49 IF data packet, since we send samples packetized in VITA. The docs would be better to say samples. -josh > ___ > Discuss-gnuradio mailing list > Discuss-gnuradio@gnu.org > https://lists.gnu.org/mailman/listinfo/discuss-gnuradio ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org https://lists.gnu.org/mailman/listinfo/discuss-gnuradio
[Discuss-gnuradio] Problem setting USRP transmitting signal power
Hi~ I found some strange problem setting USRP transmitting signal power. The method I change the transmit power is to use a constant to multiply the signals. the problem is that I use bigger constant like 2.0, the SNR value i calculate is lower than using constant like 1.0. the transmit signal values are 0.005,-0.005. my experiment platform is USRP N210 plus motherboard RFX2400. Is there anything wrong or there are better method to setting USRP transmiting power? thanks!!! -- View this message in context: http://gnuradio.4.n7.nabble.com/Problem-setting-USRP-transmitting-signal-power-tp39823.html Sent from the GnuRadio mailing list archive at Nabble.com. ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org https://lists.gnu.org/mailman/listinfo/discuss-gnuradio
[Discuss-gnuradio] AttributeError: 'module' object has no attribute 'square_ff'.
hi everyone,i have made my own block in gnuradio name square_ff from out of tree module.i hsvr successfully interfaced it with gnuradio.but problem is when i want to use that block in gnuradio then the following error i get in terminal. AttributeError: 'module' object has no attribute 'square_ff'. kindly help me ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org https://lists.gnu.org/mailman/listinfo/discuss-gnuradio
[Discuss-gnuradio] What are the actual meaning of slot_interval, guard_interval, lead_limit in TDMA engine of Pre-Cog
Hi John, I am using the TDMA engine of the Pre-Cog, and investigating the code. For some parameters in the initlization of the TDMA engine, I am wondering if i understand correctly: self.initial_slot = initial_slot self.slot_interval = slot_interval self.guard_interval = guard_interval self.num_slots = num_slots self.lead_limit = lead_limit Could you shed a light on them, especially the lead_limit. Thanks very much. -- Alex, *Dreams can come true – just believe.* ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org https://lists.gnu.org/mailman/listinfo/discuss-gnuradio
