Apparatus and method for point-to-point multipoint radio transmission

DETAILED DESCRIPTION OF THE INVENTION The present invention provides a point-to-multi-point broadband radio transmission system.
FIG.
1 illustrates an exemplary embodiment of such a system in eight story building 100.
Beam center 30 is transmitted from transmitter 20 to receiver 60e at the fourth floor window 40e.
Transmitter 20 is displaced horizontally from receiver centerline 50 a distance of 4 feet along the roof, such that line of sight relationship is obtained from the transmitter 20 to each receiver (60a .
.
.
60h).
The formula used to calculate the 4 foot distance is: the receiver diameter times the building height divided by the height between floors.
In this case the height between floors of building 100 is 10 ft.
, the height of building 100 is 80 ft.
, and the diameter of each receiver (6a .
.
.
6h) is one-half foot.
Therefore, the displacement distance would be 4 feet.
FIG.
2 is an enlarged view of one window 40a with receiver 60a.
The receiver 60a is cabled into the apartment unit associated with window 40a (not shown), which could beneficially be an RG-59 cable.
Mounting bracket 80 would secure receiver 60a to the side of building 100 (FIG.
1).
Receiver 60a would be aimed at transmitter 20 (FIG.
1).
Referring back to FIG.
1, transmitter 20 could advantageously be comprised of a broadband transmitter operating in the 50-250 Mhz range with a narrow beam, high-gain antenna.
Receivers 60a .
.
.
60h could be advantageously comprised of high-gain, low-noise receivers with a narrow beam, high-gain antenna.
Although the instant invention relates generally to a point-to-multipoint transmission system, transmitter 20 and receivers (60a .
.
.
60h) could advantageously be transceivers, allowing two-way communications capability.
Transmitter 20 and receivers (60a .
.
.
60h) could illustratively be comprised of the AIL 28 Ghz wireless Video System.
FIG.
3 describes a hypothetical power level diagram of received energy (in dBmv) from a 28 Ghz narrow-beam, low-power, solid-state transmitter at 80 foot distance at varying amounts of angular displacement on either side of the beam center