British anti-stealth technology?!

I was just taking a look at some websites when I found a article (in Portuguese) talking about a method developed by British researchers to detect stealth aircraft using mobile telephone basestations. It says that it was noted that the cellular phones’ radiation reflected by aircrafts may be detected by antennas mounted in a truck working as a bistatic system. It adds that each detecting system will cost US$200,000 each, and each one may be located 20 km far away from each other, in order to build a network. Does anyone know how much truth is this or have any further data about this?

Regards,
Junin