SDR
Software-Defined Radio

Software-defined radio (SDR) is a radio communication system where components that have been typically implemented in hardware (e.g. mixers, filters, amplifiers, modulators/demodulators, detectors, etc.) are instead implemented by means of software on a personal computer or embedded system. While the concept of SDR is not new, the rapidly evolving capabilities of digital electronics render practical many processes which used to be only theoretically possible. ~ Software-defined radio, From Wikipedia, the free encyclopedia

I have become fascinated with Software-Defined Radio (SDR). Here is a public record of my investigation into this technology. ~ C. Spangler, October 29, 2016

Current Hardware:

SDRplay RSP2pro

R820T2 RTL-SDR Dongle ~ Amazon [2 used with Outernet] ~ Amazon [1 for research, connected to a Pi 3]

FlightAware Pro Stick Plus ADS-B USB Receiver with Built-in Filter [see below] ~ Amazon

NooElec NESDR Mini SDR & DVB-T USB Stick (RTL2832 + R820T) w/ Antenna and Remote Control ~ Amazon

Yosoo 100KHz-1.7GHz Full Band UV RTL-SDR USB Tuner Receiver/ R820T+8232 ~ Amazon

Usmile® USB VHF and UHF Full band Direct RTL-SDR Receiver ~ Amazon

Current Software:

I primarily use GNU Radio / Gqrx / HDSDR / CubicSDR on Mac (OS X, Darwin, Linux) & PC (Windows, Linux)

I use SDRuno [manual, related, blog] with RSP2pro on Windows 10

I sometimes use RSP2pro with CubicSDR & API driver on MacOS X 10.11.6

Big List of RTL-SDR supported software

Web:

RTL-SDR.COM / /r/RTLSDR / sdr-radio.com / smittix.co.uk / eham.com / wiki.radioreference.com

April 27, 2017

Raspberry Pi 3, NOAA 15, 18, 19, & SDR

Continuing Work On Antennas

noaa-20170427
Click for large image

March 17, 2017

Raspberry Pi 3, NOAA 15, 18, 19, & SDR

First Image from NOAA-19 via NASA Goddard Space Flight Center
First Image from NOAA-19 ~ NASA Goddard Space Flight Center Source

For almost forty-five years I have enjoyed receiving weather satellite images from space and thought I would try using a 'stand-alone' Raspberry Pi 3 to replace a larger computer.

SDR ~ RPi3 ~ NOAA RX
Test One 201703.17: Raspberry Pi 3 ~ 4x USB Extender ~ NooElec SDR ~ EDUP WiFi

SDR ~ RPi3 ~ NOAA RX
Alternative with RTL-SDR SDR attached

Current [201703.21] SDR,  SDR~ RPi3 ~ NOAA RX
Test Two (2) 201703.22: Raspberry Pi 3 w/EDUP WiFi ~ Speaker ~ Usmile® SDR

 

I specifically followed these instructions, verbatim, provided by Jim Haslett:

Raspberry Pi NOAA Weather Satellite Receiver by haslettj in raspberry-pi

http://www.instructables.com/id/Raspberry-Pi-NOAA-Weather-Satellite-Receiver

[Video] Receiving NOAA Weather Satellites
with an SDR and a Raspberry Pi
~ Jim Haslett

https://www.youtube.com/watch?v=jukobjB46gQ

have the following in operation:

SDR ~ RPi3 ~ NOAA RX
Satellite schedule & Received Weather Satellite data

SDR ~ RPi3 ~ NOAA RX
Alternative ~ SDRplay RSP2pro ~ Yaesu FT-991

however... ;-) need to spend more time working on the antenna:

SDR ~ RPi3 ~ NOAA RX
NOAA 19 (ch 3-4, southbound 52 E) at 2017-03-17 11:13 UTC

using the following guides:

Building a quadrifilar helix antenna (QFH) for NOAA
satellite reception with an RTL-SDR
~ Jim Haslett

https://www.youtube.com/watch?v=KU75FSA6o2M

Quadrifilar Helix Antennas

http://metsat.gogan.org/ant_qha.htm


QFH Antenna Results - NOAA 19 satellite
reception with SDR
~ Jim Haslett

https://www.youtube.com/watch?v=dqmbLdudUKI

and this is good to know:

WXtoImg Upgrade Keys

http://leshamilton.co.uk/wxkeys.htm

to be continued...

March 01, 2017

realADSB icon from Nikolay Klimchuk

RealADSB & Raspberry Pi 3

Having tried most SDR related ADS-B free programs, I decided to look for an application and selected RealADSB created by Nikolay Klimchuk.

My main reason for this selection was due to our remote location and minimal television signals; resulting in the use of AppleTV, which RealADSB supports. Here is a video: RealADSB app on tvOS.

The RealADSB page shows what one needs to set this app up for Windows, MacOS X, and Raspberry Pi 2+.

For testing purposes, I started with MacOS X. [Note: Java 8 is required to use ADS-B hub]

After becoming comfortable using the app, I switched operation to a Raspberry Pi to conserve electricity.

RealADSB Steps using Raspberry Pi 3:

Step 1: FlightAware Pro Stick Plus for USB receiver

Step 2: Antennas

NooElec 1090 MHz antenna. [I use this for portable operation.]

Home-brew Compact 6dBi Collinear Antenna [I use one like this most of the time.]

ADS-B wine cork antenna

Quarter Wave antenna

Simple ADSB J-pole antenna

PCB based antenna design

PCB based strip line antenna

RealADSB, Raspberry Pi 3 ADS-B
RealADSB used with FlightAware USB~SDR & Raspberry Pi 3

Step 3: USB driver: not required for MacOS X or Raspberry Pi

Step 4: ADSB server: already had RTL_TCP running from below Cocoa1090 install

Step 5: ADSB hub: [Note: Did not have to download Java 8 for updated Raspbian Jessie.]

Step 6: Purchased RealADSB app and followed directions

Step 7: Useful links I used to make this process easier:

Installing rtl-sdr and dump1090 on a Raspberry Pi to receive ADS-B signals

ADS-B using dump1090 for the Raspberry Pi

Raspberry Pi 2 & 3 ADS-B for the RSP

Mode-S and ADS-B on a Raspberry Pi

Self-contained ADS-B receiver

Step 8: For WiFi ~ Edimax EW-7811Un 150Mbps 11n Wi-Fi USB (nano) Adapter ~ Amazon

realADSB AppleTV Screenshots from flyingsnail.com

realADSB AppleTV flyingsnail.com Screenshot
Weather Radar left over from last big storm at flyingsnail meadow... [mountain here]

realADSB AppleTV flyingsnail.com Screenshot
Without Weather Radar 201702.28

realADSB AppleTV flyingsnail.com Screenshot
With Weather Radar 201702.28

realADSB AppleTV Screenshots from Nikolay Klimchuk:

realADSB AppleTV Nikolay Klimchuk Screenshot

realADSB AppleTV Nikolay Klimchuk Screenshot

realADSB AppleTV Nikolay Klimchuk Screenshot

realADSB Nikolay Klimchuk AppleTV Screenshot

November 22, 2016

GOES-R Weather Satellite


The Future of Weather Forecasting from good news ~ https://vimeo.com/65249399


GOES-R Launch | Real-Time from Mike Augustyniak ~ https://vimeo.com/192535633

GOES-R heads to orbit, will improve weather forecasting

November 19, 2016 GOES-R, the first of NOAA’s highly advanced geostationary weather satellites, lifted off from Cape Canaveral, Florida, at 6:42 p.m. EST today. The satellite will boost the nation’s weather observation network and NOAA’s prediction capabilities, leading to more accurate and timely forecasts, watches and warnings. [Click to Continue Reading]


Meet GOES-R from NOAA_Satellites ~ https://www.youtube.com/watch?v=R3Uo859ktM8


How to Order NOAA Weather data from David Rockwell ~ https://vimeo.com/170829769


AT THE EDGE OF THE SOLAR STORM ~ 4K from AD Photography ~ https://vimeo.com/191348354

from Lets Hack It:

GOES Satellite Hunt (Part 1 – Antenna System)

GOES Satellite Hunt (Part 2 – Demodulator)

GOES Satellite Hunt (Part 3 – Frame Decoder)

GOES Satellite Hunt (Part 4 – Packet Demuxer)

GOES Satellite Hunt (Part 5 – File Assembler)

The entire working source code is at OpenSatellite Project in github.


from RTL-SDR.COM:

CREATING A GOES WEATHER SATELLITE DEMODULATOR

SETTING UP A GOES WEATHER SATELLITE ANTENNA SYSTEM

BUILDING A FRAME DECODER FOR THE GOES WEATHER SATELLITE

DEMUXING FRAMES AND GENERATING IMAGES FROM THE GOES WEATHER SATELLITE

RECEIVING GOES LRIT FULL DISK IMAGES OF THE EARTH AND EMWIN WEATHER DATA WITH AN AIRSPY

November 14, 2016

ADS-B
Automatic dependent surveillance – broadcast


Improving Air Traffic Management in the North Atlantic
from NAV CANADA ~ https://vimeo.com/133171739

ADS-B Receiver

Cocoa1090 image
Cocoa 1090 (Mac) image ~ Large Image

ADS-B is a surveillance technology in which an aircraft determines its position via satellite navigation and periodically broadcasts it, enabling it to be tracked. The information can be received by air traffic control ground stations as a replacement for secondary radar. It can also be received by other aircraft to provide situational awareness and allow self separation. From Wikipedia, the free encyclopedia

The Flightaware Pro Stick Plus SDR ADS-B receiver arrived, was set up on a Mac Mini using Cocoa 1090 software from black cat systems and rtl-tcp*, with an antenna similar to, but less expensive than, this.

The above image is just a screenshot. If one goes to rtl-sdr.com and uses ADS-B as a search term, one will see maps that can be linked, etc.

* Here are instructions via black cat systems for building rtl-tcp.

* The above step was not necessary (for me) because I had previously built and installed rtl-tcp using University of California, Berkeley's EE123 Digital Signal Processing page, which also provides Windows and Linux instructions.

rtl_tcp

My future intention is to build an ADS-B Raspberry pi.

Here is an ADS-B repository I use from SonicGoose and a Big List of rtl-sdr.com supported software.


Update: Installed ModeSDeco2 on Mac Mini using Flightaware Pro Stick Plus.

Charts, Stats, & Flights pictured at link under "Description". Personal recorded map shown below:

ModeSDeco2 Map image
Click for Large image

ModeSDeco2 and other software available for Windows, Linux, Raspberry pi 2 & 3, Odroid, CuBox, and Mac at xdeco.org.

October 29, 2016

Gqrx Ghost Box by Doug Harber
gqrx-ghostbox
A software defined radio tool for talking with the dead
by Doug Haber

Overview

[Source: https://github.com/DougHaber/gqrx-ghostbox]

This program makes it possible to use software defined radio (SDR) as a ghost box / electronic voice phenomenon (EVP) tool. A ghost box is a device sometimes used by paranormal researchers to talk to spirits, the dead, disembodied entities, shape shifting lizard people, and other intra-dimensional fauna.

Some ghost boxes have electronics that give them distinct properties, and others are effectively radio scanners. This tool is of the radio scanning style.

This utility controls the Gqrx SDR receiver program. Unlike more traditional ghost boxes, which are stand alone devices, this setup makes it easy to experiment with different options. Gqrx provides a live visualization of the spectrum and the ability to fine tune and control many parameters of the radio, such as gain, demodulation, squelch, and noise filtering. Ghost boxes usually scan AM or FM. By using SDR, we have a vastly larger spectrum available (though AM may require an upconverter, depending on which SDR is used.)

If we assume that the phenomena is a real thing, this style tool provides researchers with more options and controls than traditional ghost boxes at a lower cost. A cheap USB RTLSDR is enough to get started, and it is easy to experiment with different antenna configurations as well as radio and scanning parameters to figure out what is most effective.

If this tool works for you, please share any successful results here.


Installation and Dependencies

In order to use this program you must have a software defined radio device. A $10 RTLSDR could work, as could more expensive and capable options. For people starting out, I recommend picking an R820T2 based USB stick. Many well reviewed options can be found on Amazon for between $10 and $25 dollars. (Note that these will not support tuning the AM spectrum without an upconverter.)

Traditional ghost boxes usually scan the AM radio spectrum. With this tool you can scan any range of the spectrum that your SDR supports. Unfortunately, the cheaper SDR devices, such as what was recommended above will not receive AM. To receive AM you will either need a more capable SDR device or another device known as an upconverter.

This program is written in Perl. The only dependency beyond a recent version of Perl is the GQRX::Remote module. This may be installed via the package on GitHub, or from CPAN. Here are some notes on installing CPAN modules.

Gqrx is required, and must be setup to allow remote connections from the host this program is running on. For some notes on settings that up, see the GQRX::Remote README and Gqrx's documentation. The Gqrx application itself officially runs on Linux, MacOS and Raspberry Pi. An unofficial version exists for Windows. For more information, see the Gqrx download page.

NOTE: SDR and Gqrx are not always trivial to work with and this is a command-line tool. A final dependency would be some level of comfort working with these types of things and a willingness to tinker. If you have not used SDR, Gqrx, and the command line before, do not expect it to work without some effort.


Usage

To use this program:

Begin by running Gqrx.

You must enable remote control via Tools->Remote control. Gqrx has to be setup to allow connections from the host this program is running on (localhost, or otherwise.) The configuration options are found under Tools->Remote control settings.

In a terminal, run the gqrx-ghostbox command with any desired options.

Modify any parameters in Gqrx as needed, such as the gain, squelch, and filtering.

Enter a deep trance state and begin your communion with the spirits.

Many examples of ghost box usage can be found on youtube. Generally, it involves asking questions and then listening for a response. Some people believe a medium or trance state is necessary in order for it to work. If you search for "ghost box" or "spirit box", you will find information on different usage styles.

Command Line Options

Usage: gqrx-ghostbox [OPTIONS]

GENERAL:  
-h, --help Display this detailed help message
-q, --quiet Quiet mode - only output errors
   
CONNECTION:  
-H, -- host={IP_ADDRESS} GQRX Host IP (default is 127.0.0.1)
-P, --port={PORT} GQRX Port (default is 7356)
-h, --help Show this help message
   
RADIO SETTINGS:  

-d, --demodulator-mode={MODE}

The GQRX demodulator mode to use (default is 'WFM')

Options: AM, CW, CWL, CWU, FM, LSB, USB, WFM, WFM_ST, WFM_ST_OIRT

   
SCANNING SETTINGS:  
--min, --min-frequency={FREQUENCY} Minimum frequency to scan in KHz
(default is '88000', FM min)
--max, --max-frequency={FREQUENCY} Maximum frequency to scan in KHz
(default is '108000', FM max)
-m, --scanning-mode={MODE}

Method of scanning
(default is 'bounce')

Options: forward, backward, bounce, random

-s, --scanning-step={STEP_SIZE}

How many KHz to move when scanning (default is 150)

This has no effect in "random" mode

--S, --sleep={TIME} Time to hold a frequency for each step
in ms. (default is '30')

Usage Examples

# Run gqrx-ghostbox with the default parameters
$ gqrx-ghostbox

# Run against Gqrx on a remote server
$ gqrx-ghostbox --host=10.0.0.1 --port 1234

# Perform random scanning between 800mhz and 900mhz
$ gqrx-ghostbox --min=800000 --max=900000 --scanning-mode=random

Usage Notes

The speed of the scan is controlled by two options. The --sleep option determines how long in milliseconds the program waits after changing frequency. There is no timing loop. Instead, after an update cycles completes, the sleep is performed for the defined duration. The --scanning-step option tells how far the frequency is adjusted in KHz. Normal values would range between 50 and 500.

Scanning starts at a random point within the --min and --max frequency. When in bounce mode, the starting direction is also random.

The --scanning-mode supports 4 different options:

Mode
Description
forward Each step increase the current frequency by the --scanning-step size. When exceeding --max, start back at --min.
reverse Each step decrease the current frequency by the --scanning-step size. When exceeding --min, start back at --max.
bounce Start randomly in either forward or backward mode. When exceeding the --min or --max limit, switch to the opposite mode. (This is the default)
random Each step choose a new random frequency within the --min and --max range.

Sharing Results

If you do use this tool and have good results, please share them to help others. A GitHub issue has been created to share these details. Please include:

A description of your usage, what happened, and external links to any media

The command line options used to invoke gqrx-ghostbox

The type of hardware used (type of SDR, type of antenna, upconverter)

Any notable configuration options in Gqrx

Any other notes on your setup and usage (antenna placements, ancient ghost evocation ritual, etc)

Copyright and License

Copyright (c) 2016, Douglas Haber
All rights reserved

Redistribution and use in source and binary forms, with or without modification, are permitted provided that the following conditions are met:

* Redistributions of source code must retain the above copyright notice, this list of conditions and the following disclaimer.

* Redistributions in binary form must reproduce the above copyright notice, this list of conditions and the following disclaimer in the documentation and/or other materials provided with the distribution.

* The names names of the authors may not be used to endorse or promote products derived from this software without specific prior written permission.

THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDER AND ITS CONTRIBUTERS ''AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR ITS CONTRIBUTERS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

tl;dr:

gqrx-ghostbox: A software defined radio tool for talking with the dead

submitted by DougHaber, Reddit Source

I wrote a tool that allows you to use SDR as a ghost box. A ghost box, or sometimes spirit box, is a tool used by paranormal researchers. The simpler ones are effectively radio scanners, so it seemed like a good fit for SDR around Halloween.

The tool controls a Gqrx instance via the remote control protocol. To make this possible, I wrote a Perl module named GQRX::Remote for providing a simple interface to the Gqrx remote control protocol.

Everything is open source. Here are the links:

gqrx-ghostbox:

GitHub: https://github.com/DougHaber/gqrx-ghostbox

gqrx-remote:

GitHub:

https://github.com/DougHaber/gqrx-remote

CPAN:

http://search.cpan.org/~dhaber/GQRX-Remote-1.0.0/Remote.pm

An example using gqrx-remote to plot signal strength by frequency:

https://github.com/DougHaber/gqrx-remote/tree/master/example/



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