| 摘要 |
PURPOSE: A wireless microphone using 60GHz is provided to enable frequency cell division without generating the false cross with other wireless microphones using an identical frequency band, by perceiving that an absorption rate of 60GHz band frequencies to the air is relatively high. CONSTITUTION: In a transmitting unit(200), a 60GHz up-converter(9) composed of a mixer, a VCO(Voltage Control Oscillator) and an amplifier is added next to an RF(Radio Frequency) signal amplifier(4) for transceiving signals at an 60GHz frequency band. In a receiving unit(250), a 60GHz down-converter(10) composed of a mixer, a VCO and an LNA(Low Noise Amplifier) is added between an antenna(6) and a signal amplifier(7). In the 60GHz up-converter(9) and down-converter(10), a frequency oscillation semiconductor device is a PHEMT(Pseudomorphic High Electron Mobility Transistor) device, in which a gap between a drain and a source is shallow to a level of few micrometers, a contact width between a gate and a plate upper surface is made smaller than the gap, and the number of fingers of the gate is 2 or 3.
|
