| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide multi-mode communication equipment which prevents a low noise amplifier of a receiving system from being deteriorated and destroyed by leaking a transmission signal outputted from a transmission system of one communication system to the receiving system of another communication system, and can obtain excellent receiving sensitivity, the multi-mode communication equipment being capable of dealing with a W-CDMA scheme and a GSM scheme. <P>SOLUTION: The multi-mode communication equipment comprises a switch element, which is connected between an input unit of a low noise amplifier constituting a receiving system of each of communication systems of the W-CDMA scheme and the GSM scheme and a ground and can be selectively turned on/off by a control signal and a control circuit for controlling the ON/OFF of the switch element. During transmitting operation of one communication system, the switch element provided in the input unit of the low noise amplifier in the receiving system of another communication system is controlled to be turned on, such that the input unit of the low noise amplifier is brought into low impedance and a transmission signal to be leaked is suppressed, thereby preventing a device such as a low noise amplifier from being deteriorated and destroyed. <P>COPYRIGHT: (C)2008,JPO&INPIT</p> |
