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Wireless opperation explained for owners



Lets look a little to the Wireless Alarm System communication
principles and see how they are "obliged" to operate.

I will explain here "data collisions" Radio Frequency Interferences
(RFI) and more by making a reduced and SIMPLE ANALOGY between the
wirelesses "BURST" transmission principle and an example using private
car parking slots.

Note:  Find between brackets the related items of the wireless
       data handling technique.

- In a parking lot there are several locations available but
  each one slot is assigned for a certain purpose, car, van..
  (radio frequency spectrum assignment by FCC++);

- One or several parking slots are assigned, some are larger but
  still made available in an economical justified available
  space, there is a large number of requests and only limited
  space avail in the parking lot (frequencies are more and
  more crowded, request for large space is limited and defined
  by the nature of the requested space, TV for example);

- In order to extend (+/-) the assigned parking slot handling
  capacity, the parking slot is shared by several owners of that slot.
  They can be shared only and when each car is present during a
  limited time span (RF burst communication) and none is occupying
  it continuously (audio RF transmitter).

- When two or more car's try to park at random time on the
  same parking slot and the parking slot occupation is not planed
  (asynchronous RF transmission), there are parking slot occupation
  collisions.
  Each party has to wait that the parking slot is free by trying
  to get access at it later on when there is no longer somebody having
  access to that slot (free time between transmission bursts).

- Parking slot's can minimize interference due to access
  collision problems by narrowing car size (RF receiver bandwidth).
  Lets assume that the assigned parking slot can handle and hold
  two "small" cars beside each other, the possible interference
  between car's is reduced by that figure.

- A car parked in the middle of a dual parking slot jeopardizes,
  even with a small car the parking slot multi handling capacity
  (RF transmitter not tuned precisely).

- Parking slot collisions can be reduced if parking slot size
  increases (wide RF band allocation and frequency occupation
   synchronized, not allowed for wireless alarms by FCC).

I'll stop here this simplified analogy.
I hope this help to understand the RF data communication technology
used in wireless alarm systems, called burst transmission (only
scratched).

NOTE:
"So called pro's" in that wireless alarm business obviously don't
possess the meager intellectual capacity required to understand the
simplistic concepts of what I write.
 Don't overestimate theyre talent to judge others either.



Paul



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