摘要:
A portable electronic apparatus is disclosed having an antenna and a communication circuit. The antenna impedance is chosen to be a predetermined value which is deliberately mismatched to the impedance of the communication for a predetermined frequency band. This mismatch is chosen to optimize the signal loss between the antenna and the communication circuit when the antenna is far and near a disturbing source. The imaginary part of the antenna impedance has a sign opposite to the sign of the circuit impedance when the antenna is a predetermined distance from the disturbing source.
摘要:
A radio transmission system comprises a phased-array radio apparatus for optimizing reception in a multipath transmission environment. In the phased-array radio apparatus, phase shifting is performed after down-conversion of received RF signals. Phase control and beam-forming are simple. By applying a zero-IF or low-IF receiver structure, the complete structure can easily be fully integrated.