Summary of Spoofing GPS is it really the time we think it is, and are we really where we think we are ?

00:00:00 - 00:25:00

The video discusses GPS and its increasing use in various sectors, including financial trading, highlighting the concern over the accuracy of the time data that GPS delivers. The speaker examines the concept of GPS spoofing, which can now be achieved through readily available software-defined radio. The video explores the limitations of the software and its need for optimization, and the power requirements and ranges for its use. The speaker also questions the reliability of GPS for civilian use, considering the potential for spoofing attacks. The video also proposes methods to detect spoofing, including using the angle of arrival of a signal to counter spoofing and computer-efficient techniques like magnifying spectrum energy. Lastly, live measurements on a b210 are presented to demonstrate the efficacy of spoofing GPS in gaining a detailed understanding of GPS signals.

• 00:00:00 In this section, the speaker presents an overview of GPS and how it works as a set of spaceborne atomic clocks that generate high stability reference signals. The presentation then shifts to the topic of GPS spoofing, which can now be achieved using readily available software-defined radio. The talk explains that while GPS has become a crucial tool for many activities, including financial trading, there is a growing concern over the accuracy of the time data GPS distributes. The speaker questions whether GPS time can be trusted and presents the case of how financial institutions use GPS to synchronize time-stamp trades with microsecond accuracy.
• 00:05:00 In this section, the speaker describes a method of GPS spoofing using RINEX files to obtain satellite data, and a software called PlutoSDR to generate a virtual constellation of satellite data to spoof GPS. The speaker explains the limitations of the software and its need for optimization, and the power requirements and ranges for its use. The speaker also describes the efficacy of the method on mobile phones and drones with U-blox receivers, which provide raw data and indicators for spoofing and jamming.
• 00:10:00 In this section, the video discusses GPS spoofing and the stability of GPS clocks. The clock provided with a Pluto SDR can be off by a few parts per million (ppm), however, GPS clocks can never be offset by more than plus or minus 5/2 Hertz. The video explains that they remove the quartz from the Pluto SDR and fed it with a hydrogen maser, which is a very high stability clock. The issue arises with the local oscillator, which is why some cars can resist spoofing. The video then explains how to improve this by replacing the temperature control crystal oscillator with an oven-controlled crystal oscillator. By doing this, the stability of the system is improved by four orders of magnitude.
• 00:15:00 In this section, the speaker discusses the stability of GPS and how spoofing can affect it. They explain that short term stability pertains to frequency, not time, and show a graph displaying the stability of the on-board rock at different frequencies. The speaker then introduces the concept of spoofing time using GPS, but notes that this would not affect one's position since the whole constellation is jumping over time. They go on to discuss the implications of relying on GPS for civilian use, and question whether it can be considered reliable given the potential for spoofing attacks.
• 00:20:00 In this section, the speaker questions the trustworthiness of GPS systems and discusses ways to detect spoofing. The common anti-spoofing techniques such as Doppler and power adaptations are considered unreliable and easily adaptable by powerful attackers. The speaker proposes that the angle of arrival of a signal can be used to counter spoofing, as demonstrated by the use of multi-antenna arrays and detecting angle of arrival in a special issue of GNSS sensitivity to attacks in 2016. However, the speaker admits that the technology used in a study was too complicated for him to understand. To simplify the GPS signal detection process, Paul Boffin presented a computationally efficient method that involves collecting data streams and squaring every signal to collapse the spectrum energy in one peak, which raises the magnitude by 30 dB, making the signal visible if it is better than -130 dBm.
• 00:25:00 In this section, the speaker presents live measurements on a be 210 that demonstrate the use of spoofing GPS to show a detailed understanding of GPS signals. He notes that by removing the BPSK modulation, you can be left with only the geometrical phase. Looking at the plot of the phases of the spoofing signal, one can see that all the satellites are at the same location, which is not possible since they should be at different locations. The speaker discusses his computationally efficient solution using the b210 and concludes that spoofing GPS is a good opportunity to demonstrate a detailed understanding of GPS signals.