Hi All,

Ultrasound sensors set to passive mode can detect motion sensors and other ultrasound sensors in active mode. There is no indication to what range this works at or how accurately you can pinpoint the source. Any ideas?

What about ultrawideband radar? Can this be detected? Does it require another ultrawideband radar system or will a simple radar detector work?

And a final question; is there a mechanical version of the echolocation bioware?

Thanks

Sensors use the Signal range tables to determine their effective probing range; I'd say within that range you could pick up their signal. I suggest using a system analogous to detecting hidden wireless nodes; electronic Warfare+Sensor[Complex Action, 4] extended to pinpoint a specific semi-known one, and [16] to locate all hidden active sensors in the area.




It can certainly be detected. I think UWBR uses a different frequency band than Radar, so I'd say not with the Radar detector.



There's ultrasound cyberware isn't it? Echolocation is basically bioware ultrasound.

I would say for the ultrasound, the range is determined by the active sensor. The passive sensor is not sending anything out, so it will only trigger when the active ultrasound's active sensing connects the 2 devices (so to speak).

Almost, except that ultrasound is using specific frequencies and thus, can be looked for. Same with ultarwideband radar. Echolocation uses any, or nearly any, sounds and could theoretically be changed at random to confuse anyone looking for active scanning. Maybe even mimicking sampled ambient noise so that active scanning blends in to the environment.

At least that's my current theory.

Ultrawideband and ultrasound are great but like active wireless networks that don't belong they would be something I'd look for if I had a security system.

I don't see why you couldn't also detect, say, rhythmic clicking of biological echolocation with properly accessorized microphone sensors. Using 'sample ambient noise' sounds a little too technological for echolocation, but a suitably restrictive house rule might allow it (eidetic sense memory required, or something).

Most say UWB can't be detected, or at least the source's location not detected. I agree with current technology, but with the sort of sensor sensitivity and processing power needed to make UWB work with such resolution as it does in SR4, it seems obvious that you can also calculate the position of an UWB source. Still, lots of people bashed me in another thread for saying that turning on an UWB radar is like broadcasting your position through walls.

For biological echolocation I would agree. However if there was a technological version then sampled ambient noise should be doable. Of course there would have to be a technological version but I'd have to think with 4E technology it would be easy to do.

You could defeat a lot of microphone sensors just by changing what sounds you are using for the echolocation each time. With the proper hearing augmentations on the echolocation sensor you could use sounds outside of normal hearing ranges and everything in between.

That's kind of what I was looking for. It just seems to me that the other active sensors would be too easy to detect.

Well I think per the rules they might be correct since I can't find anything on sensor detection but I kind of agree with you, assuming someone is looking for a given sensor type.

Sure, you might need multiple sensors to triangulate a position but in some cases all you need to know is that there is a source; especially if there's not supposed to be one. Let a security team handle the rest.

I guess for my own game I'll treat it like ultrasound. UWB set to passive mode can detect active UWB systems within signal range.

Yeah, just knowing someone else in the area is using UWB is plenty of intel.

In secure areas, detecting a UWB 'ping' that isn't one of yours should be a red flag that you're being breached.

Also, a radio signal scanner should be usable to detect radar, if set properly, as radar uses radio waves.



-karma

I'd say you can't see pick up say terahertz from a Radar Sensor with a radio signal scanner anymore than you can pick up visible light with one. Sure, they're all electromagnetic radiation, but the hardware that can pick it up is very different.

The RSS is just for wireless communications.

I don't think I'd allow an RSS either but given Rand's input above, even a R1 UWB would be useful as a passive detector since it would be the active sensors signal rating that determined detection range.

The RSS is good enough as it is.

Yes, I agree that a UWB can detect UWB emission.

Honestly, I can't tell what the RSS even does. It says it's a Sniffer, but its functions are those of a Scan and/or Trace, and some of the things the fluff says it does aren't even allowed.

My own interpretation would be that an active sensor can be detected at twice it's effective range : the signal is strong enoug hthat it can travel to the limit ot detection and bounce back - hence being still within detection range after twice the range traveled and possibliy some attenuation - some signal is lost in the bounce.

Just like using a lamp into the night, going active makes you detectable farther than you can detect.

That's a good idea for a house rule, or possibly 1.5x effective range is more fair. Either way, it's not really the RAW.

Motion sensors also use ultrasound, and they have an explicit ruling: "Intruders may detect the ultrasonic field by using an ultrasound sensor set to passive mode within 5 meters."

I was thinking along the same line of thought actually. I wasn't set on max detection range but twice works. I was sure that it would be farther than the effective range of the active sensor.