Diversity receiving system in portable radio equipment

Abstract

Abstract PURPOSE:To secure communication of a good quality even if it is influenced by a using state and Rayleigh fading, by providing at least two antennas of an electric field type and a magnetic field type on a portable radio equipment, and selecting suitably an antenna having a good receiving level. CONSTITUTION:A demodulating signal is rectified through a squelch circuit 40, and compared with an output of a reference voltage generator 50. In case when the output of the reference voltage generator 50 is smaller, an ''L'' signal is outputted from a comparator 60, and a control part 70 sends out a non-switching signal to a switching device 30. In case of the contrary, an ''H'' signal is outputted from the comparator 60, the control part sends out a switching signal, and a loop antenna 2 is selected. A low frequency amplifier 45 becomes an operation holding state by a holding circuit when an output signal of the comparator 60 is in an ''H'' level, and an audible sound in case when a quality of a receiving signal is deteriorated is inhibited.

Inventors

• 👤 Akio Goto
• 👤 後藤　昭夫
• 👤 Kazuhisa Yamamoto
• 👤 和央 山本
• 👤 Tomoo Ishikawa
• 👤 石川　倫男

Bibliographic Details