RADIO COMMUNICATION DEVICE AND RADIO COMMUNICATION METHOD

• US 20120052819A1
• Filed: 02/23/2011
• Published: 03/01/2012
• Est. Priority Date: 03/02/2010
• Status: Active Grant

• Current Assignee: Panasonic Corporation (Panasonic Holdings Corporation)
• Original Assignee: Panasonic Corporation (Panasonic Holdings Corporation)
• Inventors: Sato, Junji, Fujita, Suguru
• Granted Patent: US 8,824,975 B2
• Time in Patent Office: Days
• US Class Current: 455/78
• CPC Class Codes: H03F 1/3247 using feedback acting on predistortion circuits H03F1/3264 takes precedence
• CPC Class Codes: H03F 1/34 Negative-feedback-circuit arrangements with or without positive feedback H03F1/02 - H03F1/30, H03F1/38 - H03F1/50, H03F3/50 take precedence ; for rejection of common mode signals H03F3/45479
• CPC Class Codes: H03F 3/24 of transmitter output stages
• CPC Class Codes: H03F 3/245 with semiconductor devices only
• CPC Class Codes: H03F 3/604 using FET's
• CPC Class Codes: H04B 1/0475 with means for limiting noise, interference or distortion H04B1/0483 takes precedence
• CPC Class Codes: H04B 2001/0433 with linearisation using feedback

Abstract

It is provided a radio communication apparatus and radio communication method that, in the radio communication apparatus having a normal transmitting/receiving mode and a distortion correction mode, communicates successfully without influencing circuit characteristic in a normal transmitting/receiving mode, sends back a transmitting signal from the receiving system, extracts a distortion component due to narrowband characteristics or non-linear characteristics of a circuit, and corrects distortion in a distortion correction mode. In radio communication apparatus (100), distortion detecting section (111) extracts a distortion component using a transmitting baseband signal and a receiving baseband signal, coupling degree adjustment circuit (180) adjusts the degree of coupling between transmitting antenna (130) and receiving antenna (140), and coupling degree control section (170) switches the degree of coupling depending on a normal transmitting/receiving mode or a distortion correction mode.

Claims

1. A radio communication apparatus that has a normal transmitting/receiving mode and a distortion correction mode, the apparatus comprising:

a transmitting circuit that includes a transmitting processing circuit that generates a high frequency signal from a transmitting baseband signal by radio transmitting process and a power amplifier that amplifies the high frequency signal;

a transmitting antenna that transmits the high frequency signal amplified by the power amplifier;

a receiving antenna that receives the high frequency signal transmitted by the transmitting antenna;

a receiving circuit that includes a low noise amplifier to amplify the high frequency signal received by the receiving antenna and a receiving processing circuit to generate a receiving baseband signal by demodulating the high frequency signal amplified by the low noise amplifier;

a distortion detecting section that detects a distortion component using the transmitting baseband signal and the receiving baseband signal;

an adjustment section that adjusts an degree of coupling between the transmitting antenna and the receiving antenna; and

a control section that switches the degree of coupling depending on the normal transmitting/receiving mode or the distortion correction mode.

2. The radio communication apparatus according to claim 1, further comprising a gain control section that controls a gain in at least one of the power amplifier or the low noise amplifier,

wherein the control section controls the degree of coupling to allow a strength of a signal to be sent back from the transmitting antenna to the receiving antenna to have a level not to produce distortion in the receiving circuit, based on the gain provided by the gain control section.

3. The radio communication apparatus according to claim 1, wherein:

a ground is arranged between the transmitting antenna and the receiving antenna; and

the adjustment section comprises;

a passive element; and

a switch that is arranged between the ground and the passive element.

4. The radio communication apparatus according to claim 1, wherein:

a ground is arranged between the transmitting antenna and the receiving antenna; and

the adjustment section comprises;

a passive element; and

a variable capacitance that is arranged between the ground and the passive element.

5. The radio communication apparatus according to claim 1 wherein an electric field surface of the transmitting antenna and an electric field surface of the receiving antenna are arranged to face each other.

6. The radio communication apparatus according to claim 3 wherein the transmitting circuit, the receiving circuit, and the switch are formed by a monolithic microwave integrated circuit.

7. The radio communication apparatus according to claim 1, wherein:

the transmitting antenna is formed by a plurality of antenna elements;

the adjustment section is formed by a plurality of phase shifters, where the plurality of phase shifters are provided between the plurality of antenna elements and the power amplifier; and

the control section controls the degree of coupling by adjusting the phase of the plurality of phase shifters.

8. A radio communication method that is applied to a radio communication apparatus to have a normal transmitting/receiving mode and a distortion correction mode, the method comprising:

generating a high frequency signal from a transmitting baseband signal by radio transmitting process;

generating a transmitting signal by amplifying the high frequency signal;

sending the transmitting signal;

outputting as a received signal after receiving the transmitting signal;

amplifying the received signal;

generating a receiving baseband signal by demodulating the amplified received signal;

detecting a distortion component using the transmitting baseband signal and the receiving baseband signal;

adjusting an degree of coupling between a transmitting antenna and a receiving antenna; and

switching the degree of coupling depending on the normal transmitting/receiving mode and the distortion correction mode.