Radio frequency signal transceiver device capable of enhancing transmission and reception performance of mobile communication device

1. A receiver of a mobile device comprising:

an antenna for receiving signals;

a first switch comprising a first end coupled to the antenna, a second end, and a third end;

a filter coupled to the third end of the first switch;

a second switch comprising a first end, a second end and a third end, the second end of the second switch coupled to the second end of the first switch, and the third end of the second switch coupled to the filter;

a low noise amplifier coupled to the first end of the second switch for amplifying the signals received by the second switch; and

a control circuit for controlling the first and the second switches to selectively pass the signals through the filter.

2. The receiver of claim 1 further comprising:

a frequency down-converter coupled to the low noise amplifier for down-converting frequencies of signals outputted from the low noise amplifier; and

a signal processing circuit coupled to the frequency down-converter for performing signal processing.

3. The receiver of claim 1 , wherein when power of the signals is lower than a predetermined level, the control circuit controls the first and the second switches without passing the signals through the filter.

4. A transmitter of a mobile device comprising:

a signal processing circuit for generating signals;

a second switch comprising a first end coupled to the signal processing circuit, a second end, and a third end;

a filter coupled to the third end of the second switch;

a antenna;

a first switch comprising a first end coupled to the antenna, a second end coupled to the second end of the second switch and a third end coupled to the filter; and

a control circuit for controlling the first and second switches to selectively pass the signals through the filter.

5. The transmitter of claim 4 further comprising:

a frequency up-converter coupled to the signal processing circuit for up-converting frequencies of signals outputted from the signal processing circuit; and

a power amplifier coupled to the frequency up-converter for amplifying power of received signals and sending to the second switch.

6. The transmitter of claim 4 , wherein the mobile device is a mobile phone, when inputting an emergency number to the mobile phone, the control circuit controls the first and the second switches without passing the signals through the filter.

7. A mobile device comprising:

an antenna for receiving and transmitting signals;

a signal processing module comprising a baseband module, a receiving module, and a transmitting module;

a first switch;

a second switch comprising a first end coupled to the antenna, and a second end coupled to the first switch;

a first filter coupled to the first switch;

a second filter coupled to the first switch;

a third switch comprising a first end coupled to the signal processing module, a second end coupled to the second switch, and a third end coupled to the first filter;

a fourth switch comprising a first end coupled to a signal processing module, a second end coupled to second switch, and a third end coupled to the second filter; and

a control circuit for controlling the first switch, the second switch, the third switch, and the fourth switch.

8. The mobile device of claim 7 , wherein the signal processing module comprises:

a frequency down-converter for down-converting signal frequencies for the baseband module; and

a low noise amplifier comprising a first end coupled to the third switch, and a second end coupled to the frequency down-converter.

9. The mobile device of claim 7 , wherein the signal processing module comprises:

a frequency up-converter for up-converting frequencies of signals outputted from the baseband module; and

a power amplifier comprising a first end coupled to the fourth switch, and a second end coupled to the frequency up-converter.

10. The mobile device of claim 7 further comprising a third filter coupled between the first filter and the third end of the third switch.

11. A mobile device comprising:

an antenna for selectively receiving and transmitting signals;

a signal processing module comprising a baseband module, a receiving module, and a transmitting module;

a first switch;

a first filter coupled to the first switch;

a second switch comprising a first end coupled to the receiving module, a second end coupled to the first switch, and a third end coupled to the first filter;

a third switch;

a second filter coupled to the third switch;

a fourth switch comprising a first end coupled to the signal processing module, a second end coupled to the third switch, and a third end coupled to the second filter;

a fifth switch comprising a first end coupled to the antenna, a second end coupled to the first switch, and a third end coupled to the third switch; and

a control circuit for controlling the first switch, the second switch, the third switch, the fourth switch, and the fifth switch.

12. The mobile device of claim 11 , wherein the receiving module comprises:

a frequency down-converter for down-converting signals frequencies for the baseband module; and

a low noise amplifier comprising a first end to the second switch, and a second end coupled to the frequency down-converter.

13. The mobile device of claim 11 , wherein the transmitting module comprises:

a frequency up-converter for up-converting frequencies of signals outputted from the baseband module; and

a power amplifier comprising a first end coupled to the fourth switch, and a second end coupled to the frequency up-converter.