5
5.
Antenna integration
The choice of antenna is important to maximizing the coverage area of the
RIM 801D radio modem. It is important to choose an antenna that will best
compliment the needs of a specific project. There are many different
antenna options that will meet both your gain and directivity requirements
and remain within budget constraints.
Three well-known antenna
manufacturers that have experience with DataTAC frequencies are Larsen,
Austin Antenna and Antenna Technology Inc. (Please see -
Appendix II for contact information). Research In Motion Limited can also
provide antenna design services.
Antenna requirements
The RIM 801D OEM Radio Modem transmits on frequencies between
806 MHz to 825 MHz. Receive frequencies are between 851 MHz and
870 MHz.
Antenna gain
Antenna gain is dependent on the radiation pattern, antenna match, and
antenna efficiency. Antenna gain is a rating of the maximum increase in
radiated field energy density relative to an ideal isotropic radiator,
expressed in decibels (dB) of power gain.
An isotropic radiator is an unrealisable theoretical reference for measuring
antenna gains and patterns. It is based on a 100% efficient point source
