Questions tagged [sdr]

Software Defined Radio is a technology for doing radio signal synthesis and demodulation/analysis using software.

Filter by
Sorted by
Tagged with
0
votes
0answers
18 views

Is this antenna compatible with the HackRF One?

I am purchasing a directional WiFi antenna to be used with the HackRF One SDR platform to do some signal processing. Before proceeding I want to make sure that these devices are electrically ...
2
votes
1answer
39 views

creating IQ data for LMS6002D SDR

I have an FPGA connected to an LMS6002D SDR from Lime micro. I also have an BladeRF board which I am using to help me verify the functionality. I starting out with trying to create IQ data for BPSK ...
0
votes
1answer
29 views

LMS7002M: I & Q DATA formats from LIMESDR

Can any one tell me what is the data format of LMS7002m I & Q sample? Are they unsigned int or floating or double? how are they ? Also kindly anyone show me any hint of proof for their answer.... ...
1
vote
4answers
233 views

How can I record RF?

For audio I can use just sound card, plus OS api to record any signal from 20 hz (below that's blocked via capacitor) to 96khz(that's half of max samplerate). But what if I just want to go higher? As ...
-2
votes
2answers
60 views

Is it possible to replicate a Novotron 522 remote control?

The signal I want to replicate is to open/close a garage door, operated by a Novoferm motor. The remote control used is a Novotron 522. The description states this is 2-channel remote control, ...
0
votes
0answers
69 views

Automate sequence of different remote control presses

I've got the following setup I would like to automate: Press button A on a remote to turn the alarm system off Press button A on a remote to open the garage door Press button A on a remote to close ...
0
votes
0answers
46 views

What kind of Modulation? Who transmits on 850 MHz (LTE-Uplink or GPRS?)?

Hey, I found an interesting Signal on 850MHz (in Germany). It is not symmetric and very strong (relative to many others due to bad antennas). On the right side the bandwith is permanently used, on the ...
0
votes
0answers
42 views

Correct way to calibrate SDR RX into a measuring receiver

While playing with my SDR (Software Defined Radio) Board, I was interested in performing a TX output power table at different center frequencies and TX antenna gains. However, unfortunately, I do ...
1
vote
1answer
61 views

Correct way to compute the power of a pulsed signal

I'm developing an application with my SDR Board and I've managed to produce a calibration table to verify the output power of the transmitter for every TX configuration of antenna gain and IQ digital ...
0
votes
0answers
24 views

Output TX Power with complex impedances

I'm developing an application with my software defined radio (SDR) Board and it is very critical that I have some control over the actual power I am transmitting at every time. In order to do this, I ...
0
votes
0answers
70 views

Manchster Decoding when symbol are misaligned

Have this problem: I can manually easily decode this using Manchester: It will be 01010100001 etc However how should I decode this: It should be a start sequence code. However on the first ...
0
votes
0answers
109 views

Keyfob decode using GNU Radio Companion

Found this project to decode Hella Keyfobs https://github.com/bastibl/gr-keyfob Try to decode mine, but somehow the signal is way different from the one from the above Repo. From the repo: Mine: ...
1
vote
1answer
98 views

SDR Signal Generator Frontend

I am working on a board that can take the output of an SDR (or VCO) and provide high accuracy amplitude control (+- 0.5dB). This is an opensource project that I will hopefully launch on crowdsupply ...
0
votes
0answers
39 views

How to resolve error in sending user data to USRP's SDRu transmitter function?

I'm trying to send user defined data over USRP board using SDRu Simulink blocks available. Following is the block diagram of my model: Basically right now I'm trying to use the USRP board as a ...
1
vote
2answers
72 views

Signal Strength to ADC quantisation levels

According to the excellent site of AB4OJ, the Icom 7300 in summary has a 14bit analogue to digital converter with a 1.5 volt peak to peak input (LTC2208-14). I make this to be 91.5uV per quantisation ...
0
votes
1answer
219 views

Effects of impedance mismatch on RF signals from antenna

I'm building an antenna array that operates at high frequencies (around 2 GHz). I want to use a SDR dongle that has a 75 ohm input impedance as receiver, I've also bought the coax cable, a 4 way ...
0
votes
1answer
81 views

How can I measure my smartphone transmitted power? [closed]

I was wondering if I can measure my phone's transmitted power with an SDR by tunning in the transmission bandwidth but then, I'm not sure how to know whether this power is coming out of my phone or it'...
0
votes
1answer
44 views

Identification of line code from amplitude, phase and PSD plots

I recorded some transmitted data using the Noo-Elec RTL2832 software-defined radio. The data is transmitted at a carrier frequency of 1.3GHz and sampled at 2.4MHz. The transmitted data is a set of ...
0
votes
2answers
140 views

Measure transmission power of USRP [closed]

I am working with USRP(Universal Software Radio Peripheral) having power gain (mentioned in specifications) of 17dBm to 20dBm. I am using 3dbi omni-directional VERT900 antenna with it. I know the ...
1
vote
0answers
113 views

Help decoding line code

I have collected a burst signal from a radio device using an RTL-SDR and gnuradio and demodulated the FSK, but am having trouble deciphering what the line code is. Signal is at 151.3MHz Here is the ...
3
votes
2answers
583 views

Expected peak-to-peak output voltage of satellite LNB

Anyone know what the output voltage of a typical DirecTV LNB might be? I've converted an old dish to be a backyard radio telescope and I'm hoping to record output levels with a USB oscilloscope, as I ...
0
votes
0answers
46 views

Checking for signals above strength threshold over SDR on VHF

So I have a small NooElec Software Defined Radio and I've got it working well with my Raspberry Pi using GQRX as a controller and to visualize the SDR output. My goal though is to use a python script ...
-4
votes
1answer
83 views

SDR usage and safety [closed]

I am considering to purchase an RTL SDR dongle for some hobby purposes, but I have some questions regarding health safety and instructions, if any, that are to be adopted. This is the dongle that I'm ...
-2
votes
1answer
205 views

Software defined cell-phone detection [closed]

I want to at least detect devices that are using 2G, UMTS or LTE. What would be the basic stuff, in terms of hardware and software, for that? I assume gnuradio or some Universal Software Radio ...
2
votes
1answer
110 views

How to observe the signals of a radio remote control using CubicSDR?

I have to admit I'm a complete newbie with regards to radio frequencies and such ... :-( Thanks to this site I've been able to find out what transceiver is being used in the remote control I'm ...
0
votes
1answer
834 views

Interpreting IQ Data (as hex) from an RTL-SDR/Hack-RF

I am wondering if someone can shed some light on how to meaningfully interpret I/Q data that is produced from an RTl-SDR dongle (RTL2832U) using the Osmocom RTL-SDR library. I have used I/Q data ...
0
votes
1answer
117 views

Can we transmit a PSK modulated signal with YARD Stick One?

We are working on a project to produce a simple walkie talkie repeater. We have a RTL SDR, which we are using to reverse engineer our signal. Using this + URH, we think our signal is PSK modulated, ...
0
votes
1answer
229 views

What is the difference between IF data and IQ data? How we can read IF data in SDR? [closed]

How to read IF data in GNU SDR? As i had tried a lot to read IF data in SDR but it can be readable in MATLAB but not in SDR..
0
votes
0answers
236 views

Reading Radio Frequency signal in audacity

I am wanting to read radio signal I captured with my RTL-SLR, I record it in .wav file using SDR#, The Frequency was at 315MHz. I am what I believe is the preamble of the signal, and I would like ...
-1
votes
1answer
70 views

Equivalent circuit for a radio power source (USRP)

I have a radio signal source (USRP N210 with a WBX daughterboard) that can supply a maximum power of 100mW. I am designing a power amplifier for it and I would like to simulate the radio signal source ...
2
votes
0answers
193 views

ETSI EN 300 220-2 vs ERC 70-03 Limitations

I’m trying to understand discrepancies between EN 300 220 and ERC regarding the use of 865 - 868 MHz spectrum for SDR. Current ERC 70-03, page 8, says: Frequency Band: h1.2 Maximum Occupied ...
10
votes
1answer
2k views

What could this signal at 119.9 MHz be?

I had some fun with an RTL-SDR dongle, and I noticed this weird signal with no noticeable pattern at 119.9 MHz. What's even weirder is that the signal is symmetrical. What might this be? Or is ...
1
vote
1answer
358 views

Maintaining phase continuity of LO when switching from Tx to Rx mode

I am building a two-way communication setup based on software defined radios. Setup: The Tx needs to send a sinusoid to the Rx, and the Rx - after some processing - sends its own sinusoid in return. ...
-1
votes
3answers
798 views

Antenna preamplifier [closed]

I'm designing an antenna preamplifier for my SDR Receiver. I checked some designs online but I decided to set for simple transistors as I have no source for JFETs and battery powered to make it ...
0
votes
2answers
81 views

Differential QPSK receiver

The communications channel between a QPSK transmitter and receiver can introduce an arbitrary phase change. For this reason, differential QPSK is used. Differential QPSK seeks to solve the phase ...
-2
votes
1answer
245 views

Simplest FM Radio Spectrum Capture Hardware Without Demodulation [closed]

I am trying to build a FM receiver circuit with simplest elements, transistors, capacitors (an op-amp such as LM 741 would be fine too) for analysis purposes (not real-time radio). The circuit should ...
2
votes
1answer
357 views

High precision distance between two GPS devices (may be GNSS-SDR)

I wish to get to high precision distance between 2 not moving points. e.g. 1 cm accuracy for distance 1 km I think if I will catch same GPS signal in two points then distance between resulting ...
20
votes
2answers
524 views

“56k modem” found in VHF band

While scanning the VHF spectrum with a SDR USB dongle, I found something that sounded like an old 56k modem (at around 160MHz, FM modulation, Europe region). After some research, I found out that is ...
1
vote
3answers
1k views

Where does SDR IQ data come from?

I have never really done much RF design before, and am looking into getting an SDR and messing around with it. I have been doing some research into how they work, and havr found that IQ modulation and ...
3
votes
0answers
151 views

bearing ambiguity resolve (direction finding) for multiple sources

I am working on wideband direction finding algorithms for passive sensors. I started with Music algorithm. For practical reasons, the spacing can not be maintained lambda/2. For greater antenna ...
0
votes
1answer
227 views

Determining the bit rate on a real-time USRP implementation

I'm transmitting a 16-QAM signal using an NI 2920 USRP. Here is a snapshot of the front panel that is seen (on LabVIEW) - I'm trying to figure out the bit rate from the given details. The symbol rate ...
2
votes
5answers
574 views

Software Defined Radio hardware

Most software defined radio peripherals involve a FPGA. In designing a SDR peripheral, I would like to know whether its possible to design a GNU Radio Compatible SDR hardware peripheral without any ...
1
vote
3answers
1k views

How to use the same antenna to receive and transmit on the same frequency with an SDR [Half-Duplex]?

Considering that the SDR board has one TX/RX output/input and one RX input, I am wondering how could I use one antenna for a half duplex communications on the same frequency. The idea is to use the ...
3
votes
2answers
556 views

SDR pcb design guide [closed]

I am searching for any type of guides for pcb design for SDR (software defined radio) application without luck. I am planning to design pcb board with Zynq-7000 and AD9364 onboard. Any recommendation ...
1
vote
1answer
161 views

Replacing 28.8Mhz TCO with up-converted GPSDO 10Mhz signal?

Would it be possible to design a circuit that could replace the TXCO (28.8Mhz) of a RTLSDR dongle by replacing it with a signal generated from a 10Mhz reference signal, coming from a GPSDO? And what ...
2
votes
2answers
1k views

Antenna for broadcast AM reception on ARM Radio SDR

I'm trying to build the ARM Radio project detailed here. I routed and fabricated a PCB for the anti-alias filter and preamplifier shown on page 2 of the linked PDF, and reproduced here: Unfortunately ...
6
votes
2answers
352 views

limit duration 1pps signal

As a beginner in electronics, I would appreciate very much to get some input from you folks for my project, so I can decide in what direction to point my nose :) What would I like to do? I would ...
3
votes
1answer
149 views

Can I implement a FM Radio Rx on the the Spartan 3E kit?

Can I implement a FM Radio Rx on the the Spartan 3E kit? Starting Problems I am facing- How do I interface the Antenna with the Spartan 3E kit? Implementing the A/D converter.