Multiple input multiple output transceiver

1. A multiple input multiple output (MIMO) transceiver comprising:

a baseband radio frequency (RF) chip for conducting RF signals; and

an RF transceiver circuit, comprising:

a first antenna and a second antenna, the first and second antennas receiving and transmitting the RF signals;

a first receiving channel connected between the first antenna and the baseband RF chip;

a second receiving channel connected between the second antenna and the baseband RF chip;

a first transmitting channel connected between the baseband RF chip and the first antenna, and comprising a first power amplifier and a first transmission line which are connected together in series;

a second transmitting channel connected between the baseband RF chip and the second antenna, and comprising a second power amplifier;

a first single pole double throw (SPDT) switch, wherein a common terminal of the first SPDT switch is connected to an input of the second power amplifier, a first terminal of the first SPDT switch is connected to an input of the first power amplifier through a second transmission line, and a second terminal of the first SPDT switch is connected to the baseband RF chip; and

a second SPDT switch, wherein a common terminal of the second SPDT switch is connected to an output of the second power amplifier, a first terminal of the second SPDT switch is connected to an output of the first power amplifier through a third transmission line, and a second terminal of the second SPDT switch is connected to the second antenna;

wherein in response to the common terminal of the first SPDT switch being connected to the first terminal of the first SPDT switch and the common terminal of the second SPDT switch being connected to the first terminal of the second SPDT switch, the first power amplifier, the second power amplifier, the second transmission line, and the third transmission line cooperatively act as a balance power amplifier.

2. The MIMO transceiver of claim 1 , wherein in response to the common terminal of the first SPDT switch being connected to the second terminal of the first SPDT switch and the common terminal of the second SPDT switch being connected to the second terminal of the second SPDT switch, the first transmitting channel, the second transmitting channel, the first receiving channel, and the second receiving channel cooperatively function as a multiple input multiple output device.

3. The MIMO transceiver of claim 2 , wherein the first receiving channel and the second receiving channel transmit a beamforming signal collectively formed by the first antenna and the second antenna.

4. The MIMO transceiver of claim 3 , wherein the baseband RF chip comprises:

a smart antenna adapter, calculating an optimal phase with the best radiation performance between the first antenna and the second antenna; and

a digital signal processor, adjusting the phase between the first antenna and the second antenna according to the optimal phase and thus keeping the phase delay between the first antenna and the second antenna at a fixed value, thereby forming the beamforming signal and increasing a receiving gain of the first antenna and of the second antenna.

5. The MIMO transceiver of claim 4 , wherein the fixed value is 0.7λ, and λ is the wavelength of the RF signals transmitted or received by the first and the second antennas.

6. The MIMO transceiver of claim 1 , further comprising at least another RF transceiver circuit.

7. The MIMO transceiver of claim 1 , wherein the RF transceiver circuit further comprises:

a first sequence switch, wherein a common terminal of the first sequence switch is connected to the first antenna, a first terminal of the first sequence switch is connected to the baseband RF chip through the first receiving channel, and a second terminal of the first sequence switch is connected to the baseband RF chip through the first transmitting channel; and

a second sequence switch, wherein a common terminal of the second sequence switch is connected to the second antenna, a first terminal of the second sequence switch is connected to the baseband RF chip through the second receiving channel, and a second terminal of the second sequence switch is connected to the baseband RF chip through the second transmitting channel.

8. The MIMO transceiver of claim 7 , wherein in response to the first antenna and the second antenna receiving the RF signals, the common terminal of the first sequence switch is connected to the first terminal of the first sequence switch, and the common terminal of the second sequence switch is connected to the first terminal of the second sequence switch.

9. The MIMO transceiver of claim 7 , wherein in response to the first antenna and the second antenna receiving the RF signals, the common terminal of the first sequence switch is connected to the second terminal of the first sequence switch, and the common terminal of the second sequence switch is connected to the second terminal of the second sequence switch.

10. A multiple input multiple output (MIMO) transceiver comprising:

a baseband radio frequency (RF) chip for conducting RF signals; and

a plurality of RF transceiver circuits, each of the RF transceiver circuits comprising:

a first antenna and a second antenna, the first and second antennas receiving and transmitting the RF signals;

a first receiving channel connected between the first antenna and the baseband RF chip;

a second receiving channel connected between the second antenna and the baseband RF chip;

a first transmitting channel connected between the baseband RF chip and the first antenna, and comprising a first power amplifier and a first transmission line which are connected together in series;

a second transmitting channel connected between the baseband RF chip and the second antenna, and comprising a second power amplifier;

a first single pole double throw (SPDT) switch, wherein a common terminal of the first SPDT switch is connected to an input of the second power amplifier, a first terminal of the first SPDT switch is connected to an input of the first power amplifier through a second transmission line, and a second terminal of the first SPDT switch is connected to the baseband RF chip; and

a second SPDT switch, wherein a common terminal of the second SPDT switch is connected to an output of the second power amplifier, a first terminal of the second SPDT switch is connected to an output of the first power amplifier through a third transmission line, and a second terminal of the second SPDT switch is connected to the second antenna;

wherein in response to the common terminal of the first SPDT switch being connected to the first terminal of the first SPDT switch and the common terminal of the second SPDT switch being connected to the first terminal of the second SPDT switch, the first power amplifier, the second power amplifier, the second transmission line, and the third transmission line cooperatively act as a balance power amplifier.

11. The MIMO transceiver of claim 10 , wherein in response to the common terminal of the first SPDT switch being connected to the second terminal of the first SPDT switch and the common terminal of the second SPDT switch being connected to the second terminal of the second SPDT switch, the first transmitting channel, the second transmitting channel, the first receiving channel, and the second receiving channel cooperatively function as multiple input multiple output.

12. The MIMO transceiver of claim 11 , wherein the first receiving channel and the second receiving channel transmit a beamforming signal collectively formed by the first antenna and the second antenna.

13. The MIMO transceiver of claim 12 , wherein the baseband RF chip comprises:

a smart antenna adapter, calculating an optimal phase with the best radiation performance between the first antenna and the second antenna; and

a digital signal processor, adjusting the phase between the first antenna and the second antenna according to the optimal phase, to keep the phase delay between the first antenna and the second antenna at a fixed value, to form the beamforming to increase a receiving gain of the first antenna and the second antenna.

14. The MIMO transceiver of claim 13 , wherein the fixed value is 0.7λ, and λ is the wavelength of the RF signals transmitted or received by the first and the second antenna.

15. The MIMO transceiver of claim 10 , wherein the RF transceiver circuit further comprises:

a first sequence switch, wherein a common terminal of the first sequence switch is connected to the first antenna, a first terminal of the first sequence switch is connected to the baseband RF chip through the first receiving channel, and a second terminal of the first sequence switch is connected to the baseband RF chip through the first transmitting channel; and

a second sequence switch, wherein a common terminal of the second sequence switch is connected to the second antenna, a first terminal of the second sequence switch is connected to the baseband RF chip through the second receiving channel, and a second terminal of the second sequence switch is connected to the baseband RF chip through the second transmitting channel.

16. The MIMO transceiver of claim 15 , wherein in response to the first antenna and the second antenna receiving the RF signals, the common terminal of the first sequence switch is connected to the first terminal of the first sequence switch, and the common terminal of the second sequence switch is connected to the first terminal of the second sequence switch.

17. The MIMO transceiver of claim 15 , wherein in response to the first antenna and the second antenna receiving the RF signals, the common terminal of the first sequence switch is connected to the second terminal of the first sequence switch, and the common terminal of the second sequence switch is connected to the second terminal of the second sequence switch.