Powerline Geolocation

The electrical transmission lines used to transmit power are optimized for 50 to 60 Hz waveforms, but are suitable for waveforms of higher frequencies, into the megahertz range. Therefore, powerline conductors are capable of transmitting signals which could be used for geolocation. Indeed, frequencies in the 100 kHz range are used for diagnostic purposes in contemporary power grids today. Signals transmitted in this band are used to verify the operation of sites along the power grid, are used to configure the power grid (for example, throw a circuit breaker). The technology takes advantage of the suitability of electrical conductors employed in power transmission for signal transmission in the sub-megahertz range, and, in the preferred embodiment, utilizes the existing diagnostics signals in this range for geolocation. The technology leverages the electrical conductors employed in power transmission for signal transmission for geolocation. Unmanned aerial vehicles have the capability to inspect high-voltage conductors and associated structures from points of view that are not available to ground-based or helicopter-based crews. In order to geolocate its position, such a vehicle relies on one or more navigation systems including: GPS, inertial measurement unit systems (IMUs), or image recognition. Geolocation accuracy via image recognition suffers from changes in lighting (e.g., time of day and weather variations) and from changes in the scene (e.g., foliage changes in spring vs. winter). Inertial systems suffer from positional drift which currently occurs on the order of minutes for compact systems. GPS suffers from multipath affects near metallic structures (which are ubiquitous in transmission line infrastructure), from satellite loss due to horizon blockage (the stadium effect), from electromagnetic interference on the radio band of GPS transmissions, and, most fundamentally, from loss of the GPS transmission by the orbital satellites. Powerline conductors are capable of transmitting signals which could be used for geolocation to aid in navigation.