A Smarter Antenna

Abstract

The Isotropic radiator, a device capable of radiating energy evenly in all directions is an abstraction, itsʼ real counterpart is called an omnidirectional (omni) antenna. The omnidirectional antenna is found on many vehicles. Ideally, only one receiving system is ever needed to acquire an omni, no matter the vehicle orientation, given the range is not excessive. There are trade-offs with antenna efficiency, with gain typically around -15 dBi (95% coverage). This paper proposes abandoning this paradigm. If a vehicle knows where the ground is why radiate energy up into the sky, where there are no receiving stations. This can be achieved by integrating some instrumentation with a discrete antenna array so that it radiates only from selected elements. The accuracy required is modest, an inexpensive Inertial Measurement Unit (IMU) is sufficient to improve link margin by 10, 20dB or more. These numbers are credible, as outlandish as they are, and substantiated in this paper. Ironically, from the ground this non-isotropic antenna looks very isotropic. Of significant benefit, this Smarter Antenna concept enables spatial discrimination and with that comes spectrum efficiency gains beyond that achieved by other means including advanced modulation formats.