It is not a trivial effort so “feasible” will depend on the time and money you are willing to invest, and what you hope to gain by developing your own.
We have an investment of at least 20 man years in RTLS algorithm development here at Ciholas. The seeming simplicity of the mathematics when first examined belie the true complexity of the real world in these systems.
A TDoA/ToA system requires some concept of global time. That is, you have to establish how to convert the time of arrival of a tag packet measured in the anchor local time to a universal global time shared in the entire system. There is no practical hardware solution to this (even sending clock signals via cables doesn’t work), so it requires modeling the local anchor clocks against a global time reference. This alone requires in depth understanding of crystals and oscillators to accomplish.
If your system will grow to any size, you also have to synchronize anchors that can’t hear each other directly. One clumsy solution is to divide your space into clumps of anchors and a tag moves between zones, which introduces problems at the boundaries. A more elegant solution is a distributed mesh time sync system with a uniform system wide concept of precise time so that there are no zone boundaries and a tag smoothly moves among the anchors. That is what we do, it can work with hundreds of anchors spread over huge areas, but it was a non trivial project to develop and test that. Testing, in particular, can be enormously time consuming and costly since you have to do it at scale for it to have meaning.
There are similar complexities with anchor communication, occlusion mitigation, system configuration and monitoring, data weighting, non linearity, position noise, etc, etc. Many of the challenges are not obvious at the start.
Realistically, developing your own TDoA/ToA system won’t be feasible unless you have a big project that can afford the time and money to develop it in house. If you have a special need, the best bet is to find a provider who can customize their existing solution to provide it.
Mike Ciholas, President, Ciholas, Inc
3700 Bell Road, Newburgh, IN 47630 USA
+1 812 962 9408