There is much better hardware out there. The Ubertooth devices can pick up BLE, and can also plug into basically any antenna you want. It's been a while since I played with it, but a few years ago my ubertooth was grabbing LAPs without difficulty. It's not a dirt-cheap device (150$ all in) but is open and available from a variety of sources.

https://github.com/greatscottgadgets/ubertooth/wiki/Capturin...