Senstar Corporation 24000 User Manual

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E6DA0209-001, Rev B
Senstar-Stellar and the Senstar-Stellar logo are trademarks of Senstar-Stellar Corp. Copyright © 2002. All rights reserved. 
The information in this application note is subject to change without notice. Printed in Canada.
Senstar-Stellar Corporation
119 John Cavanaugh Drive
Carp, Ontario
Canada K0A 1L0
Telephone: +1 (613) 839-5572
Fax: +1 (613) 839-5830
Website: www.senstarstellar.com
Senstar-Stellar, Inc.
43184 Osgood Road
Fremont, CA
USA 94539
Telephone: +1 (510) 440-1000
1-800-676-3300
Fax: +1 (510) 440-8686
email: info@senstarstellar.com
Senstar-Stellar Limited
Orchard House
Evesham Road
Broadway, Worcs.
U.K. WR12 7HU
Telephone: +44 (1386) 834433
Fax: +44 (01386) 834477
Senstar GmbH
Riedheimer Str. 8
88677 Markdorf
Germany
Telephone: +49 (7544) 95910
Fax: +49 (7544) 959129
Senstar-Stellar Latin America
Pradera No. 214
Col. Pradera
Cuernavaca, Morelos
62170, Mexico
Telephone: +52 (777) 313-0288
Fax: +52 (777) 317-0364
Heavy snow areas
Snow accumulation decreases the effective mounting 
height. This moves the operating point toward 
destructive phasing, which could result in degraded 
performance. To compensate for snow accumulation, the 
setup of the upper unit should be changed as follows:
Select the height of the upper pair to be at a point of 
destructive phasing midway between two nodal 
lines. (As snow accumulates, the effective mounting 
height will decrease and the operating point will shift 
toward an area of constructive phasing).
Check the signal strength of the upper unit 
according to the product manual. If the signal 
strength meets the specification for proper 
operation, do NOT adjust the mounting height. If the 
signal strength is below the specification, reduce the 
mounting height in small increments, until the signal 
strength meets the minimum specification.
Ensure that both units of each pair are in a correct 
line-of-sight adjustment.
Advantages of microwave stacking
increased zone height
increased Probability of Detection (PD)
(There is double coverage from the two pairs for 
most of the zone.)
With an X-Band, K-Band combination, the lower 
K-Band unit is more sensitive to slow-moving, and 
crawling intruders. 
The upper X-Band unit is more sensitive to faster, 
upright intruders. This combination provides 
increased detection against both types of intruders
Disadvantages of microwave stacking
The cost is almost doubled
The probability of nuisance alarms is increased
If the lower unit is a K-Band microwave, there may be 
an increase of nuisance alarms from rain and snow
There is a greater potential for interference between 
microwave pairs
Because the upper unit is so high above the ground, 
its operating characteristics (received signal) can 
change from constructive phasing (strong received 
signal) to destructive phasing (weak or no received 
signal) with a slight change in mounting height 
(Although the mounting height is optimized during 
installation, snow accumulation changes the effective 
mounting height. Therefore, during a snowstorm as 
the snow accumulates on the ground, the operation 
of the upper microwave pair can become unreliable. 
Some measures can be taken during installation to 
anticipate this effect. However, sufficient snow 
accumulation will severely affect performance.)
Conclusion
For most installations, the mounting height and 
detection coverage of Intelli-WAVE will provide sufficient 
protection against bridging attempts, as long as the 
recommendations for zone coverage overlap are 
followed correctly.
When the stacking of bistatic microwave sensors is 
required, Senstar-Stellar recommends the use of two 
Intelli-WAVE (MPS 4100) X-Band units:
Intelli-WAVE is easily field-configured
Intelli-WAVE antenna elements are field-rotatable
Intelli-WAVE will have fewer nuisance alarms from 
weather effects than an X-Band, K-Band combination