I am busy with a project where I want to harvest energy from UHF and VHF such as tv broadcasts, radio and cell phone towers to charge a 100uf capacitor to be able to power a low power appliance such as a cell phone.
My plan is to use a polarized match linear antenna and using the theory and maths of friis equation I expect to get 10-100 mv.
How do I work out or know what the gain will be in dBs?
What should the antenna width be to give me a wavelength impendance of 50ohms to minimize reflection loss with a matched RF-DC charge pump circuit?
The incoming power transduced across the antenna is RF and would induce a very low voltage across the antenna terminal , so how would I rectify and step this voltage up to 3.5v-4v?
If you have any tips or advice please let me know, as well as if you think im on the wrong track. Your help is appreciated.