| 摘要 |
An antenna apparatus for backscattering an incoming radio frequency (RF) signal includes an antenna for backscattering the incoming RF signal in accordance with a reflection coefficient characteristic of the antenna. A variable impedance circuit includes an output electrically connected to the antenna. A low pass delta sigma modulator is coupled to the variable impedance circuit and digitally controls the output of the variable impedance circuit, such that the reflection coefficient of the antenna is adjusted based on the output of the variable impedance circuit. |
