Today’s cars are heavily festooned with a multitude of sensors, many of them focused on internal parameters and hard-wired into the vehicles nerve system. Whether having so many sensors is a good idea or has become too much of what started out as a good thing – well, check back in a decade or two and we’ll have the benefit of hindsight.
But cars are also adding sensors and connectivity that reaches beyond the vehicle’s immediate envelope. Cars now also may have radar for adaptive cruise control, left/right sensors for adjacent lane guidance, GPS receivers, and automatic high-beam dimming, to cite a few “reach out” areas. Coming soon, if predictions are to be believed, smart cars will also add vehicle-to-vehicle (V2V) communication, which the US National Highway Traffic Safety Administration (NHTSA) says “enables vehicles to wirelessly exchange information about their speed, location, and heading. The technology behind V2V communication allows vehicles to broadcast and receive omni-directional messages (up to 10 times per second), creating a 360-degree ‘awareness’ of other vehicles in proximity.” (There have been many articles about this technology in EDN and EE Times , of course.)
All this well-intentioned external connectivity and sensing brings new risks. Obviously, there is a significant chance of ambient-area interference and EMI/RFI causing misleading signals and readings – that’s the “easy” one to figure if not fully overcome.
What can be more worrisome is the very real possibility of various forms of deliberate jamming, which would either blind the car or yield deceptive readings. If this sounds familiar, that’s not surprising. Military systems (air, sea, land) have long used electronic countermeasures (ECM – not be confused with the car’s Engine Control Module) to hide or spoof an enemy’s radar and other sensors.
The first passive, non-electronic countermeasure was deployed in the early days of radar during WWII, with simple “chaff” (thousands of small strips of aluminum foil) dropped from planes to create false, static radar echoes. Soon, countermeasures became electronic and increased in sophistication, with an active system which returned false echoes, delayed echoes, mimicked various signals, and dynamically adapted to the parameter’s proving signal. Today, ECM is a major subsystem and many analog components are dedicated solely to the ECM unit (high-resolution, wideband A/D converters, sensitive front ends, log amps, to cite a few).
How does this relate to cars? See this recent, highly-readable, eye-opening article in Analog Dialogue , the self-published technical journal of Analog Devices. The article, “Automotive Radar Sensors and Congested Radio Spectrum: An Urban Electronic Battlefield?,” discussed some of the underlying technical issues such as waveforms, FFTs, and sweep times related to denial jamming (where a jamming signal raises the noise floor and so makes targets disappear) and deceptive jamming (where a carefully created jamming signal creates a false target), Figure 1 . Perhaps driving a car may become an exercise in ECM as much as actually getting from point A to point B, regardless of where it is on the autonomous car scale of 0 to 5.
These are some of the critical waveforms and timing diagrams for both denial and deceptive jamming. (Image source: Analog Devices)
The ECM road map may show that in a few years most cars have basic ECM. Will there be dedicated ECM modules in the car within a decade or two? Will car makers issue regular ECM software upgrades as the jamming gets more sophisticated with ever-more advanced jamming signals? Will there be an independent aftermarket offering improved ECM modules (somewhat analogous to overclocked PC CPUs), which contain not only enhanced algorithms in their firmware but also faster, wider-bandwidth A/D converters plus analog front ends offering faster converters, lower noise, and smarter filters?
I certainly don’t know, but the next cycles of car designs may evolve to resemble, at least electronically, a military vehicle. Were the Saab car ads of the 1960s and 1970s (Figure 2a and Figure 2b ), which conveyed the message “we at Saab make good jet fighters, so we also make good cars” prescient in an unintended way? (see Reference ).
Saab car ad of the (a)1960s
Saab car ad of the (b)1970s
Figure 2(a and b): These decades-old Saab auto ads were an attempt to create a comfortable, confident feeling about their technology sophistication by aligning the cars with their jet fighters. (Image source: Pinterest)
But what is likely to happen is that the ECM and counter-ECM battle will escalate, and bring with it a demand for more and better analog and mixed-signal components. Of course this won’t be cheap, both in terms of R&D or actual hardware costs.
What’s your view of the actual risk of car-jamming signals and the steps that the industry and car owners will have to take to deal with them? Will it be yet another case of never-ending upgrades and their consequences (tangible costs, compatibility, and general headaches). We have learned to live them (somewhat) for our many present devices (PCs, smartphones, smart appliances, and more). Will we accept them in our cars?
Autoweek, “The Saab 92: Born from Flying Barrels”