LIDAR (Light detection and ranging) technology generates extremely accurate terrain and obstacle models for use in RF planning.
Following strong customer demand and buoyed by the exciting news in 2015 that the UK Environment Agency were going to release terrabytes of UK LIDAR data at 2m, 1m, and lower we have been busy working behind the scenes to integrate LIDAR, starting with DSM (digital surface model) 2m resolution, which at 54,000 pixels per degree is 15 times more accurate than our current offering of 3600 pixels per degree (30 metre resolution).
LIDAR mapped from an aircraft is a huge improvement on the legacy SRTM terrain data which was mapped by radar in 2000 from the space shuttle. The higher fidelity comes at a price as the data is expensive and generally confined to urban areas or areas of special commercial interest like an open mine or major development. A major advantage of DSM over legacy DTM is the inclusion of ground clutter such as buildings and trees. The image below shows areas of no coverage which coincide with undeveloped countryside which is understandable when you weigh up the cost of chartering a plane. These not spots can be addressed with onward processing like interpolation and smoothing algorithms.
Case study: Emergency services in a city
In the UK the emergency services use the TETRA 450MHz band for communications. In this example, a low power TETRA repeater was placed on top of a large municipal building in a city mapped with 2m LIDAR DSM data. The resulting coverage shows off the accuracy of the data as well as the increased contrast between hot and cold coverage areas compared with radar mapped DEM. Crucially it reveals radio shadows on the far side of major buildings which would be best avoided for mobile stations.
We've extended the 'signal server' engine to support LIDAR and at the time of writing it is still undergoing regression testing as it is one of the most significant changes we've made. In 2016 we're going to release the update (v2.7) to the open source engine which will support reading LIDAR tiles in ASCII grid format and integrate LIDAR into the CloudRF API and interfaces for premium customers. Initially we'll focus on hosting UK LIDAR data but thanks to the use of open information standards by the Environment Agency, customers with licensed LIDAR data for anywhere in the world will be able to upload and use their own.