The utilization of digital television and radio signals for atmospheric science

Lead Research Organisation: University of Bath
Department Name: Electronic and Electrical Engineering


One of the major difficulties with using computer models to forecast the weather is keeping the models constantly updated with what the weather is actually doing. There have been enormous advances in recent years that have considerably improved the ability of numerical weather prediction models. The models are able to ingest all manner of weather observations; measurement on the ground, measurements from space, measurements from weather balloons to name a few. However, the computer models will only ever be as good as the input data that is used to represent the state of the atmosphere. As the resolution and ability of the models improve, (related to the size of the grid) to get the benefit of the model improvement, the input data must also be improved. Particularly important in computer modelling is the transportation of moisture in the atmosphere since this is a key factor in the formation of severe rain storms which can lead to flooding. Currently there is almost no instrument capable of making routine remote measurements of moisture in the lower few kilometres of the atmosphere over an area the size of the UK. With the grid-length of computer models used in research as small as 1 km, the search is on to find instruments that can provide measurements on a similar scale in order to get the very best results from the model. The aim of this project is to develop an inexpensive instrument that can measure moisture in the atmosphere. A key novelty of this proposal is that it makes use of existing digital radio and television signals broadcasts. The basic concept is simple: the more water vapour along the path between the transmitter and receiver, the longer it takes for the signal to travel. Assuming the location of the receiver is kept fixed, changes in the signal time can be related to changes in water vapour. To accomplish this there are many technical challenges that first need to be solved. The radio signals were not designed to be used in this way so a consdiderable amount of signal processing is required. In addition because the time of flight of the signal is very small it is difficult to measure and requires a very stable clock. The advantage of this approach is that it is inexpensive, consumes relatively little power and requires no additional signals to be transmitted in order to make the measurements.


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Description Exploration of the use of signals of opportunity for the use of remote sensing of refractive index parameters, which is linked to relative humidity. From such data it may be possible to better predict the occurrence of thunderstorms.
Exploitation Route There has been a follow-on grant to extend the same ideas to atmospheric electricity science.
Sectors Agriculture, Food and Drink,Construction,Electronics,Environment,Retail,Transport

Description Met Office now have a programme to look at signals of opportunity. Follow-on bid by Athena Space Limited and University of Bath to ESA EOI programme.
First Year Of Impact 2018
Sector Electronics,Environment,Healthcare,Transport
Impact Types Societal,Economic

Description Tech Proof of Concept
Amount £114,805 (GBP)
Funding ID NE/L012669/1 
Organisation Natural Environment Research Council 
Sector Public
Country United Kingdom
Description CCLRC Rutherford Appleton Laboratory 
Organisation Rutherford Appleton Laboratory
Country United Kingdom 
Sector Academic/University 
Start Year 2005
Description Chronos 
Organisation Chronos Technologies Limited
Country United Kingdom 
Sector Private 
PI Contribution Timing test equipment and advice
Collaborator Contribution IP under license, knowledge transfer
Impact GNSS jamming related products
Start Year 2008