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Security fence project - cameras & microwave detectors

Security fence project - cameras & microwave detectors

Security fence project - cameras & microwave detectors

(OP)
Hi all
I kindly need your input on a project I am doing. I am upgrading a 4KM (6m wide) perimeter security infrastructure around a high-security premise. The client does not have a problem spending money on a decent upgrade that will replace the existing 25 years old infrastructure.
The existing system consists of 56 analogue cameras, microwave detectors, coaxial cable network, 8 field PLCs, a master PLC and video recording units. Fence intrusions are detected by microwave detectors and relayed to the master PLC in the control room by field PLCs. Images from the camera closest to the intrusion are then recorded by the a video recorder.
 Use of cameras for motion detection has been completely ruled out, and hence the client insists that the new upgrade must use the existing operation philosophy (Cameras + microwave detectors). Reason being that microwave detectors may be used to protect the fence should the camera system be down on a fault.
I suggested to him that we replace the entire system with addressable cameras, new microwave detectors, fibre-optic back-bone and server(s). This will eliminate PLCs, old cameras, old detectors, coaxial cables and video recorders.
A supplier also told me that I can purchase addressable microwave detectors that will run on a software separate from the camera system.
Question:-
• Is this the right way of tackling the project?
• How good/reliable are addressable microwave detectors over ordinary type? In other words can an investment on addressable microwave detectors over ordinary ones be justified?
• What else do I need to watch-out for when considering microwave detectors?
Thanks a lot.
 

RE: Security fence project - cameras & microwave detectors

Microwave detectors are jammable that makes them useless.  Are you stopping entry (fort knox) or exit (prison)?

Motion detector infrared camera's are a good idea, why anyone would rule them out is odd, you can't jam infrared motion detectors very easily.


kch

RE: Security fence project - cameras & microwave detectors

(OP)
It's a fort type security infrastructure consisting of three high-barbed-wire fences, microwave detectors and CCTV.  One needs to jump over the outer razor sharp fence to tamper with the microwave detectors.
The customer is paranoid about motion detection cameras because seven different companies tried in vain to install such a system. Apparently valuables like wind, hail, insects, car beams from a near-by road etc were the cause of failure. I do understand his frustration and focus is to restore the system as soon as possible, then more motion detection trials can follow later.
 

RE: Security fence project - cameras & microwave detectors

Do you know about fiber-optic motion sensor technology? You run a fiber (in a conduit) around the perimeter, and if anyone tries to climb the fence (or do anything that disturbs the fiber in the slightest), the system will pin-point their location.

Ethernet (video IP) cameras are becoming more common.

 

RE: Security fence project - cameras & microwave detectors

Microwave detectors don't need to be touched to defeat. RF energy through the airwaves can make them unusable. Can't say much more other than don't count of them as a guarantee.

Ve1BLL, interesting concept, I've worked with single mode fiber optic transmission, it's very sensitive to bending but it might be unsensitive to a careful and slow fence climber. Worth a look though MotoRex.

My company has software development programs on motion detection that can avoid the normal motion pitfalls. We're considering this software as a commercial product in the near future, but are developing it for non commercial entities (government). I can say we can detect motion on the ground from an aircraft (UAV), and can detect people and objects in the ocean from a boat. To say the least, those are much more complex than a stationary camera looking for people, especially when seagulls fly across your vision on a windy day and don't get a "detection" signal.

kch

RE: Security fence project - cameras & microwave detectors

The fiber optic systems I've read about are apparently off-the-shelf and reportedly very sensitive. Not to mention cheaper than almost anything else. So I've heard...
 

RE: Security fence project - cameras & microwave detectors

(OP)
Thanks a lot VE1BLL and Higgler for your helpful input.
I have not considered fibre-optic motion sensing, what we looked at is a fence-mounted sensing system on the outer of the three fences but it did not fly. Reason being that the outer fence always receives a daily bang(hence nuisance alarms)from human, bikes and vehicle traffic all around the perimeter. I am guessing that the F-optic motion sensing will use the same concept as fence sensing.
The existing microwave detectors are on a secure 6m band between the outer and the 2nd fence. Therefore any sensor going off means that some one or something made over the first high fence and an investigation is necessary. You would also appreciate that 4KM is a great distance for two security guards to cover for every single alarm that goes off. So what they do is to sit in the control room and monitor the alarm. Then quickly turn to the 22" LCD monitor should the buzzer go off, only to see images from subject camera showing a cat having a go on a rat...and then they would reset the alarm. Of course the response is different if they see two guys in masks.

 

RE: Security fence project - cameras & microwave detectors

I would be pretty careful about installing new technology.  Your customer is obviously afraid of it.  Also, just because something is out there with all sorts of marketing claims, does not mean it can not be penetrated!  There are NSA guys that can "move" without "moving", if you know what I mean.  Make sure any new equipement has been fully tested out by the appropriate govt. agency!

RE: Security fence project - cameras & microwave detectors

(OP)
7 different 'movers' were given a chance in the last 3 years,and nothing other than time and money has 'moved'.
Higgler;
How would one jammed microwave detectors? Jamming antennas? Noise masking?
What are mitigation measures?
 

RE: Security fence project - cameras & microwave detectors

On jamming microwave detectors, I actually haven't worked with them specifically, but I have been in the Electronic Warfare (EW) industry and jamming radars (Electronic Attack (EA)) is standard procedure.

The poor mans approach would be to put some simple jammers (RF source, pulse generator, antenna, i.e. standard test equipment) outside your fence and for two weeks or more, start giving your detectors alot of detections/false alarms to desensitize your guards. Then if you have multiple systems, and the guards are really sick of the noisy false alarms, they'd turn off the microwave detectors. Microwave detectors, when switched off, can be measured by the intruders. Then enter quietly.  

If there are microwave detectors with UWB waveforms, that would be more difficult for intruders to jam or even detect.
UWB = ultra wide band, uses 3.1-10.6 GHz band.


kch

 

RE: Security fence project - cameras & microwave detectors

(OP)
Thank you Higgler and everyone else who assisted.

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