The programmers of SDR# have just released a new version which now includes a SpyServer directory browser. SpyServer is an Airspy and RTL-SDR compatible SDR streaming server for SDR#. It allows you to access your SDR remotely over the internet or a network connection by using efficient data compression techniques.
The new browser allows you to browse for active and publicly shared SDRs that are running SpyServer. To launch the browser in the latest SDR#, choose "SpyServer Network" in the Source drop down menu, and click on the "..." button. At the moment there are only a few servers listed, and not all work. But we expect more to show up and work as people update their SpyServer software.
For SpyServer users, the latest server version will automatically list your server in the directory, but it can be turned off in the config file.
Thank you to ON7NDR as well as CM2ESP for submitting and figuring out a way to get GOES 16 decoding working with RTL-SDR using the free XRITDecoder,Xrit2Pic software and GNU Radio for Windows.
ON7NDR's story is that he wanted to be able to receive GOES 16, but not being familiar with Linux he wanted a Windows based solution. He writes that the credit to finding the solution goes to CM2ESP who has written up a tutorial (pdf) explaining how to set everything up in Windows. ON7NDR has also written a separate complimentary tutorial (docx) that explains some steps in CM2ESPs tutorial a little further and provides a few tips on choosing correct the correct version of GNU Radio. He's also provided a screenshot showing what the correct config file looks like for an RTL-SDR dongle.
We note that for Windows there is also USA-Satcom's XRITDecoder, however this is closed source software which costs $100 USD.
Thank you to Neoklis (5B4AZ) for writing in and letting us know about his recently completed project which is a RTL-SDR compatible receiver and decoder application for the Meteor M2 weather satellite. It is a combination of other open source programs and he writes:
I combined the recently released Meteor-M2 LRPT demodulator by Davide Belloli (dbdexter-dev), and the older image decoder (translated to C) released by Artem Litvinovich (artlav), with relevant code from my own "sdrx" SDR Receiver application to create a complete monolithic Meteor-M2 Receiver and Image Decoder application, "glrpt".
Neoklis' glrpt application is available on his website www.5b4az.org under the "Weather Imaging -> Meteor M LRPT Receiver" menu. The application is open source and appears to be Linux only. In order to install it you'll need to download and compile the source code, and compilation instructions are available in the documentation stored in the doc folder. Neoklis also writes that you can find his older APT image decoder called "xwxapt" under the same Weather Imaging heading of his website.
GLRPT User Interface Showing Processed Meteor M2 Images
The Airspy HF+ and the KiwiSDR are two HF specialty SDR radios. The HF+ advertises excellent dynamic range and sensitivity, whilst the KiwiSDR has it's strength in it's internet connectivity and 30 MHz wide live bandwidth.
Over on YouTube icholakov has uploaded a video comparing the two SDRs on daytime medium wave and shortwave reception with a W6LVP amplified magnetic loop antenna. It is expected that the two SDRs should be quite similar in easy receiving conditions, but the Airspy HF+ should shine in challenging conditions with strong blocking signals and weak signals being received at the same time. The Airspy HF+ should also be a bit more sensitive in all conditions. It's not clear if there were any strong blocking signals in the tests, but the results appear to confirm the sensitivity expectations.
Netxing's idea was to use an FM transmitter connected to a computer to transmit known magnetic stripe card data via FM to the Portapack. The Portapack then receives and outputs this as FM audio to an electromagnet connected to the audio out jack, allowing it to activate the magnetic card reader.
Using this method it could be possible to make a payment by transmitting card data remotely over an FM signal. We're not sure on why you'd want to do this, but it is an interesting experiment regardless.
Lime Microsystems, creators of the LimeSDR, LimeSDR Mini and LimeNET SDR devices have recently begun crowdfunding for a new product they are calling LimeNET Micro. LimeNET Micro is described as a software defined radio platform with an integrated processor for creating self contained wireless networks. In other words it is a LimeSDR LMS7002M SDR transceiver chip with an included Raspberry Pi Compute Module 3, FPGA, GNSS module, EEPROM and Flash memory attached to it.
The LimeNET Micro is capable of full duplex TX and RX (1 port each) with the typical LimeSDR frequency range of 10 MHz - 3.5 GHz. However a major difference is that the LimeNET Micro is only capable of a 0.27 MHz bandwidth, whereas other LimeSDR products are capable of bandwidths up to 30.72 MHz. One interesting additional feature is that the LimeSDR Micro comes with a GNSS module that can be used to receive GPS/GLONASS etc for high accuracy timing if required.
Some use cases that they envision LimeNET micro being useful for include:
Inexpensive enterprise and personal networks
Rural, autonomous, and resilient networks
Universal IoT communications hubs
Rapid deployment infrastructure for emergency response
Remote radio solutions for amateur radio and radio astronomy
Integration into application-specific RF appliances
Radio spectrum survey
Passive wireless geolocation
PHY and security research
RF-aware robotics
The price is $269 USD and this includes a Raspberry Pi Compute Module 3. Higher end kits can be purchased which include Acrylic ($399) or Aluminum enclosures ($459).
LimeNET Micro with Raspberry Pi Compute 3 Module attached.
For a while now researchers at MIT and several other universities have been investigating methods for using frequencies in the WiFi bands to see through walls using a form of low power radar. The basic concept is to track and process the reflections of these signals from peoples bodies.
Recently researchers at MIT have taken this idea a step further, combining the radar results with machine learning in a project they call RF-Pose. The result is the ability to recreate and track full human post information through walls. The abstract from their paper reads:
This paper demonstrates accurate human pose estimation through walls and occlusions. We leverage the fact that wireless signals in the WiFi frequencies traverse walls and reflect off the human body. We introduce a deep neural network approach that parses such radio signals to estimate 2D poses. Since humans cannot annotate radio signals, we use state-of-the-art vision model to provide cross-modal supervision.
Specifically, during training the system uses synchronized wireless and visual inputs, extracts pose information from the visual stream, and uses it to guide the training process. Once trained, the network uses only the wireless signal for pose estimation. We show that, when tested on visible scenes, the radio-based system is almost as accurate as the vision-based system used to train it. Yet, unlike vision-based pose estimation, the radio-based system can estimate 2D poses through walls despite never trained on such scenarios.
The hope is that this technology could one day be used as a replacement for camera based computer vision. It would be a non-intrusive method for applications like gaming, monitoring the elderly for falls, motion capture during film making without the need for suits and of course for gathering data on peoples movements.
It is not mentioned in the paper, but it is likely that they are using some sort of SDR like a USRP for receiving the signals. It's possible that a lower resolution system could be set up cheaply with a HackRF and some passive radar software.
RF Pose Estimating Human Pose Behind walls using RF signals in the WiFi frequencies.Multiple people tracked with RF-Pose
As promised we announced the release to KerberosSDR mailing list subscribers first, so that they'd be the first to get the initial discounted early bird units. However due to much higher than expected interest, we have released a few "second early bird" units at a still discounted price of $115 + shipping. We're only going to release 300 of these so get in quick before the price jumps up to $125. Our pre-order campaign will last 30 days, and afterwards the retail price will become $150.
If you weren't already aware, over the past few months we've been working with the engineering team at Othernet.is to create a 4x Coherent RTL-SDR that we're calling KerberosSDR. A coherent RTL-SDR allows you to perform interesting experiments such as RF direction finding, passive radar and beam forming. In conjunction with developer Tamas Peto, we have also had developed open source demo software for the board, which allows you to test direction finding and passive radar. The open source software also provides a good DSP base for extension.
KerberosSDR with Calibration Board Attached (Metal Enclosure with SMA connectors Not Shown)KerberosSDR Main Board (Metal Enclosure with SMA connectors Not Shown)
