It is a lot of work to acquire and track the signals and this is often implemented in software. And then afterwards it takes a lot of work to calculate the navigational solution from these raw measurements.
This basically keeps a microprocessor busy which uses energy.
One trick people do for ultra-low energy non-realtime GPS tracking of wildlife is to store the “raw” radio samples and do as little processing on the tracking device as possible.[1] Then once the tracker gets back they batch process all the samples recorded and reconstruct where the animal has been. That is obviously a tradeoff of more storage used for less energy consumption. Obviously that trick does not work if you want to know where the animal is live, it can only tell you where it has been once you have processed the data.
This basically keeps a microprocessor busy which uses energy.
One trick people do for ultra-low energy non-realtime GPS tracking of wildlife is to store the “raw” radio samples and do as little processing on the tracking device as possible.[1] Then once the tracker gets back they batch process all the samples recorded and reconstruct where the animal has been. That is obviously a tradeoff of more storage used for less energy consumption. Obviously that trick does not work if you want to know where the animal is live, it can only tell you where it has been once you have processed the data.
1: https://arxiv.org/abs/2207.06310