Transmitter/Receiver Circuit and Transmission/Reception Method

• US 20090174622A1
• Filed: 12/27/2006
• Published: 07/09/2009
• Est. Priority Date: 12/27/2005
• Status: Active Grant

• Current Assignee: Kyocera Corporation
• Original Assignee: Kyocera Corporation
• Inventors: Kanou, Hideto
• Granted Patent: US 8,160,510 B2
• Time in Patent Office: Days
• US Class Current: 343/876
• CPC Class Codes: H04B 1/0064 with separate antennas for the more than one band H04B1/0053 takes precedence
• CPC Class Codes: H04B 1/48 in circuits for connecting transmitter and receiver to a common transmission path, e.g. by energy of transmitter H04B1/46 takes precedence

Abstract

There are provided a transmitter/receiver circuit and a transmission/reception method that can reduce the insertion loss of a circuit in a hybrid operation and are suitable for reducing the cost, size, and power consumption. An antenna switch 119 includes attenuation filters 201 to 203 for attenuating the frequency bands corresponding to a plurality of receiving systems, e.g., the frequency band of an 800 MHz band system, the frequency band of a 2 GHz band system, and GPS reception frequency components. These filters 201 to 203 are connected between a primary (main) antenna connection terminal T204 and a first switch group SWG201 through connection switches 204 to 206.

Claims

1. A transmitter/receiver circuit comprising:

a main antenna,

a sub antenna,

a plurality of transmission/reception systems having different frequency bands connected to the main antenna via a changeover switch,

a plurality of reception systems having different frequency bands connected to the sub antenna,

a plurality of attenuation filters connected to the transmission/reception systems via a connection switch and attenuating a plurality of frequency bands corresponding to the plurality of reception systems, and

a controlling means for controlling the connection or disconnection of the plurality of attenuation filters to the transmission/reception systems by controlling the connection switch on/off in accordance with the frequency band received at the sub antenna.

2. A transmitter/receiver circuit as set forth in claim 1, wherein

the plurality of attenuation filters are connected to transmitter circuits of the plurality of transmission/reception systems via the connection switch.

3. A transmitter/receiver circuit as set forth in claim 1, wherein

the plurality of attenuation filters are connected between the main antenna and the changeover switch via the connection switch.

4. A transmitter/receiver circuit as set forth in claim 1, wherein

the controlling means connects the attenuation filter attenuating the frequency band received at the sub antenna to the transmission/reception system in accordance with a transmission power of the main antenna.

5. A transmitter/receiver circuit as set forth in claim 1, wherein

the controlling means connects the attenuation filter attenuating the frequency band received at the sub antenna to the transmission/reception system in accordance with a reception power of the main antenna.

6. A transmitter/receiver circuit as set forth in claim 1, wherein

the controlling means measures a transmission noise generated in the transmission/reception system and connects the attenuation filter attenuating the frequency band received at the sub antenna to the transmission/reception system based on a value of the measured transmission noise.

7. A method for transmitting/receiving a plurality of signals having different frequency bands by using a main antenna capable of transmitting/receiving a plurality of signals having different frequency band and a sub antenna capable of receiving a plurality of signals having different frequency bands,

said method including:

a first step of judging whether or not an operation mode is a hybrid mode of transmitting/receiving signals of two different frequency bands by using the main antenna and the sub antenna, and

a second step of selecting and attenuating the frequency band of the signal received at the sub antenna in a transmission signal output from the main antenna.

8. A transmission/reception method as set forth in claim 7, wherein:

in the second step,

the frequency band of the signal received at the sub antenna in the transmission signal output from the main antenna is selected and attenuated in accordance with the reception power of the main antenna.

9. A transmission/reception method as set forth in claim 7, wherein:

in the second step,

the frequency band of the signal received at the sub antenna in the transmission signal output from the related main antenna is selected and attenuated in accordance with the transmission power of the main antenna.

10. A transmission/reception method as set forth in claim 7, wherein:

in the second step,

the transmission noise generated in the transmission/reception system connected to the main antenna is measured and, selected and attenuated the frequency band of the signal received at the sub antenna in the transmission signal output from the main antenna based on the measured value of the transmission noise.