In the post Akos gives an overview of the features of each dongle, and runs tests on things like frequency drift and broadcast FM interference. He also runs SNR tests on Airband, low UHF, high UHF signals and shortwave frequencies. His tests show that the dongles with the R820T2 chip outperform the dongles with the R820T chip by about 4-5 dBs in SNR, and that the overall best dongle is our RTL-SDR Blog dongle.
Over on YouTube user Adam Alicajic (creator of the popular LNA4ALL low noise amplifier) has uploaded a video showing the performance of a home made wideband helix antenna that he has created for receiving signals such as ones from L-Band Inmarsat satellites. See our tutorial for more information on receiving Inmarsat signals.
Adams helix antenna is built out of an old used can and is based on a 1.1 turn design. In the first of three videos he shows that the SWR of the antenna is all well below 2.0 from 1.5 GHz to 3 GHz. In the second video Adam shows the performance of the helix antenna on actual L-band signals being received with an RTL-SDR dongle. In the final video Adam compares the helix again a patch antenna and finds that the two receive with very similar performance.
SimpliSafe is a home security system that relies on wireless radio communications between its various sensors and control panels. They claim that their system is installed in over 300,000 homes in North America. Unfortunately for SimpliSafe, earlier this week Dr. Andrew Zonenberg of IOActive Labs published an article showing how easy it is for an attacker to remotely disable their system. By using a logic analyser he was able to fairly easily reverse engineer enough of the protocol to discover which packets were the “PIN entered” packets. He then created a small electronic device out of a microcontroller that would passively listen for the PIN entered packet, save the packet into RAM, and then replay it on demand, disarming the alarm.
A few days later Micheal Ossmann (wireless security researcher and creator of the HackRF SDR and YardStick One) decided to have a go at this himself, using a YARD Stick One and a HackRF SDR. First he used the HackRF to record some packets to analyze the transmission. From the analysis he determined that the protocol was an Amplitude Shift Keying (ASK) encoded signal. With this and some other information he got from the recorded signal, he could then use his Yardstick One to instantly decode the raw symbols transmitted by the keypad and perform a replay attack if he wanted to.
Next, instead of doing a capture and replay attack like Andrew did, Micheal decided to take it further and actually decode the packets. This took him a few hours but it turned out to not be too difficult. Now he is able to recover the actual PIN number entered by a home owner from a distance without having to do any transmitting. With the right antenna someone could be gathering 100’s of PINs over a distance of many miles. Also, an expensive radio is not required, Micheal notes that the gathering of PIN numbers could just as easily be done on a cheap $10-$20 RTL-SDR dongle.
Micheal notes that the SimpliSafe alarm seems to lack even the most basic cryptographic protection, and that this is a problem that is seen all too often in wireless alarm systems. Rightly so, Micheal and Andrew are not publishing their code, although it seems that anyone with some basic knowledge could repeat their results.
The people behind this SDR are currently marketing SoDeRa as “the Arduino of the Telecom and Radio Engineer”. It appears to be designed mainly to implement IoT and other radio communications protocols, but it also sounds like it could find excellent use in the hobby and amateur market as well as have benefits for the average person. Interestingly, the developers also plan to implement an app store which would allow you to essentially download a radio and instantly configure the SoDeRa SDR for any desired protocol or application. They write:
This is the first time that a revolutionary device for which we are organising a joint crowd-funding campaign with Lime Microsystems is made public. The #SoDeRa is the cheapest software defined radio you can buy. The #SoDeRa will have an app store and will be able to provide any type of (bi-directional) radio communication going from LTE, Lora, WiFi, GPS, Bluetooth, radar, radio-controlled toys/robots/drone, digital radio, digital TV to even MRI scanners, satellite and air traffic communications by just installing an app. The #SoDeRa is the Arduino of the Telecom and Radio Engineer.
The SoDeRa is powerful enough to be a full MiMo LTE base station with long range coverage, provided you add the right antenna. You can via apps put other wireless communication protocols like LoRaWAN, Bluetooth, Zigbee, Z-Wave, GPS, Galileo, Airspace protocols, radar, MRI scanning RF, TV/Radio, any toy/robot/drone control, White Space, etc. But most importantly because of its price and ease of adding more protocols, the SoDeRa will enable anybody to define competing wireless communication protocols and put them into Github. Developers don’t like closed standards like LTE or complex standards like Bluetooth & Zigbee. The future will allow developers to compete against corporations and standardization bodies if they think current standards can be improved upon. The Internet has shown that this dynamic brought us easier standards through adoption like JSON and Yaml vs XML and EDI. Wireless, RF and telecom engineers never had an Arduino like the electronics engineers. The SoDeRa will plug this hole.
Development on SoDeRa is working towards a trend in radio systems where all radio devices are software defined, allowing for futuristic features like advanced spectrum control and the ability to change protocols on the fly. They write:
Including #SoDeRa in any type of smart device will greatly reduce the cost of deploying a mobile base station network because by open sourcing the hardware design it will become commodity. By including software defined radio in lots of devices, often with a completely different purpose, will allow these devices to become a smart cell via installing an extra app. In the future, support for software defined radio will likely be embedded directly in Intel and ARM chips. The foundational steps are already happening. This will likely reshape the telecom industry. Not only from a cost perspective but also from a perspective of who runs the network. Telecom operators that don’t deliver value will see their monopoly positions being put in danger. As soon as spectrum can be licensed on a per hour basis, just like any other resource in the cloud, any type of ad-hoc network can be setup. The question is not if but when. Open sourcing and crowdfunding will make that “when” be sooner than later. Smart operators that align with the innovators will win because they will get the app revenue, enormous cost reductions, sell surplus spectrum by the hour and lots of innovation. Other operators that don’t move or try to stop it will be disrupted. What do you want to be?
At first glance SoDeRa sounds like it will be an expensive device, but on their official website they are currently running a survey asking people what they would be willing to pay, and the lowest price given is $50 – $99. This makes it seem likely that in the future with enough volume SoDeRa could be sold at very low cost and become very popular.
I am willing to pay for 1 unit
$50 – $99 (lead time 9 months)
$100 – $199 (lead time 6 months)
$200 – $299 (lead time 3 months)
$300 – $399 (lead time 2 months)
$400 – $500 (lead time 1 month)
It sounds like the team behind SoDeRa are gearing up for a crowd funding campaign so we will be keeping an eye on this SDR.
Thanks to RTL-SDR.com reader Serdar (TA3AS) for submitting news about SoDeRa to us.
The Meteor M N-2 is a polar orbiting Russian weather satellite that was launched in July 2014. It transmits with the LRPT protocol which allows us to receive weather satellite images that are of a much higher resolution than the NOAA APT satellites. For a while since the launch RTL-SDR users had a good time receiving beautiful images from Meteor M-N2, but unfortunately since late last year the N2 LRPT transmitter has been turned off, due to technical problems with the IR sensors as cited by Russian meteorologists.
Fortunately for Meteor N2 enthusiasts the old Meteor M N1 satellite which was thought to be dead sprung back into life around November 2015. Recently Matthew A., a reader of our blog wrote in to let us know that while N2 is still not transmitting, N1 is still transmitting, albeit with somewhat distorted images. Matthew also mentions this link: http://homepage.ntlworld.com/phqfh1/status.htm, which contains up to date info on the status of all weather satellites. He also writes:
While transmissions are readily detectable and decodable at night, it seems that M N-1’s infrared sensors are not functioning. Yielding only black, with the typical noise bars of Red, Green, or Blue
As has been previously mentioned, Meteor MN-1’s stabilization system has obviously failed, and the horizon is clearly visible. Perhaps not of scientific value, but certainly beautiful.
We also note that there are several comments over on the Meteor-M N2 news and support website regarding receiving images from N1 and N2. It seems that sometimes N1 also has some problems with transmission, but they are usually quickly fixed.
Jonti, the programmer of JAERO has recently updated his software to version 1.04 which can now be used to decode C-Band AERO signals. Previously only L-Band (1.5 GHz) AERO signals could be decoded with JAERO. C-Band signals are much harder to receive as they are at 3.6 GHz, so require an LNB, and they are also much weaker so require a large dish (at least about 1.8 meters or larger in diameter). However, the interest in them is that C-Band AERO signals arguably contain more interesting information that the L-Band AERO data. They contain actual aircraft position data which would allow you to plot the locations of all planes using that satellite. About the information that can be received Jonti writes:
The L band Aero signals (around 1.54GHz) that everyone has been decoding lately using JAERO are the very strong signals being sent from the satellites to the airplanes, this is the information that is being sent from the GESs (ground earth stations i.e. the people on the ground) to the AESs (air earth stations i.e. the people in the airplanes). A modified 2cm GPS antenna, an LNA (Low Noise Amplifiers) or two, and an SDR receiver is enough to receive such signals.
Receiving the information going the other way around from the people in the airplanes to the people on the ground is a lot more challenging. This AES to GES information first gets transmitted from the airplanes around 1.6 GHz to the satellites which is then relayed back down to the GES people on the C-band around 3.6 GHz. that means to receive information from the airplanes the only practical option is to receive the 3.6 GHz frequencies. This is above any SDR receiver I know of. To make things worse, I believe the signals are 11dB weaker than the L band ones that everyone has been receiving. Complicating matters further the signals are transmitted in bursts and each burst is dependent on the airplane’s L band transmitter. So a weaker L band transmitter on a plane produces a weaker C-band burst transmission, likewise any frequency offset of an L band transmitter on the plane produces a frequency offset on the C-band.
So what’s so attractive about C-band Aero signals?
Two reasons spring to mind. The first is the challenge of receiving and demodulating it and the second is this information contains plane location information like ADS-B (Automatic dependent surveillance – broadcast) so you can produce pretty pictures of where all the planes are in the world.
Back in December 2014 the HackRF Blue came out via a crowd funded Indiegogo campaign as a HackRF board that was $100 cheaper than the official version ($199 vs $299 USD). The HackRF is a 8-bit receive and transmit capable SDR with operating range of between 0.1 – 6000 MHz and a bandwidth of up to 20 MHz. As its hardware specifications are released as open source, it is very easy for clones of the official version to be produced. While the HackRF Blue Indiegogo campaign was successful, the product is now out of stock as they seemed to stop production after the campaign.
We are a PCB and SMT assembly factory founded in the year 2001, located in Shenzhen, China. We are a professional EMS/OEM company; provide one-stop contract electronic manufacturing service for PCB&PCBA. Now we want to make small market devices and sell directly to customers.
Some of the part on HackRF is End Of Life and very difficult to find now. We have enough of these part for ~300 HackRF only. You can find some HackRF on Alibaba right now, but they used cheap parts and the manufacture does not test them (they do not install any firmware).
We are trying to find some more of the EOL part first and will make the Kickstarter campaign soon. If we can’t find any more of these part, we will only make ~300pcs. Please register first, when we activate the campaign we will tell you by email. The first 10 people who buy from the Kickstarter will have a heavy discount, only pay $75!
Over on his blog, Twitch has uploaded a post showing how he mounted two RTL-SDR dongles into a single metal case in order to reduce noise. Twitch used a $2 aluminium metal case that he obtained from a local surplus shop and cut it down to size and added holes for switches and BNC plugs. He then mounted two RTL-SDR dongles in the case and used two MCX -> BNC pigtails to get a case mounted coax connector.
He also removed the USB plugs on the RTL-SDR’s and wired them into a USB B plug mounted to the case, making sure to wind the USB power cables through several turns of ferrite core in order to reduce USB noise. Finally he also added a power switch to the USB connections, to be able to easily power off the units when not in use.
