MICROWAVE POWER TRANSMISSION SYSTEM WHEREIN LEVEL OF TRANSMITTED POWER IS CONTROLLED BY REFLECTIONS FROM RECEIVER

• US 3,795,910 A
• Filed: 03/13/1973
• Issued: 03/05/1974
• Est. Priority Date: 03/13/1973
• Status: Expired due to Term

• Current Assignee: William J. Robinson Jr
• Original Assignee: William J. Robinson Jr
• Inventors: Robinson, William J. Jr.
• Primary Examiner(s): Gensler, Paul L.
• Application Number:
  US05/340,871
• Time in Patent Office: 357 Days
• Field of Search: 343/7.5,17.7,705 325/4,62,159,225 333/17
• US Class Current: 342/82
• CPC Class Codes: G01S 13/02 Systems using reflection of radio waves, e.g. primary radar systems; Analogous systems
• CPC Class Codes: H02J 50/20 using microwaves or radio frequency waves
• CPC Class Codes: H02J 50/27 characterised by the type of receiving antennas, e.g. rectennas

Abstract

A microwave, wireless, power transmission system in which the transmitted power level is adjusted to correspond with power required at a remote receiving station in which deviations in power load produce an antenna impedance mismatch causing variations in energy reflected by the power receiving antenna employed by the receiving station. The variations in reflected energy are sensed by a receiving antenna at the transmitting station and used to control the output power of a power transmitter.

Claims

1. A microwave power transmission system comprising:

a microwave power generator;

power supply means responsive to an input control signal for providing variable operating power to said microwave power generator whereby said microwave power generator is caused to provide an output of a selected level of microwave energy;

a power transmitting antenna adapted to receive power from said microwave power generator and direct microwave energy in an energy beam in a selected direction;

a power receiving antenna spaced from said power transmitting antenna and being positioned and oriented to receive maximum energy from said transmitting antenna;

a variable impedance, electrical, load connected to receive and use energy from said power receiving antenna;

a second power receiving antenna positioned near said transmitting antenna and adapted to receive electrical energy reflected from said first power receiving antenna;

control means responsive to the output of said second power antenna for providing said control signal to said power supply means;

whereby said power supply means is controlled and the output of said microwave power generator coordinately controlled in accordance with power requirements of said variable impedance load.

2. A microwave power transmission system as set forth in claim 1 wherein said control means is operable for providing variable control signals responsive to load values variably between a load value substantially equal to the impedance of said power receiving antenna and a selected impedance value greater than the impedance of said power receiving antenna.

3. A microwave power transmission system as set forth in claim 2 wherein said control means includes means responsive to selected combinations of load impedance-power levels of the system for providing said control signal and selected transmitter outputs for selected values of said variable impedance load.