FILTER ARRANGEMENT

• US 20120230227A1
• Filed: 03/09/2011
• Published: 09/13/2012
• Est. Priority Date: 03/09/2011
• Status: Active Grant

• Current Assignee: Kathrein SE
• Original Assignee: Kathrein-Werke KG. (Kathrein SE)
• Inventors: Weiss, Holger
• Granted Patent: US 8,723,619 B2
• Time in Patent Office: Days
• US Class Current: 370/277
• CPC Class Codes: H01P 5/12 Coupling devices having more than two ports H01P5/04 takes precedence
• CPC Class Codes: H01P 5/16 Conjugate devices, i.e. devices having at least one port decoupled from one other port
• CPC Class Codes: H03H 7/463 Duplexers
• CPC Class Codes: H03H 9/703 Networks using bulk acoustic wave devices
• CPC Class Codes: H04B 1/50 using different frequencies for the two directions of communication
• CPC Class Codes: H04B 1/52 Hybrid arrangements, i.e. arrangements for transition from single-path two-direction transmission to single-direction transmission on each of two paths or vice versa

Abstract

A filter arrangement for filtering a radio transmit signal and radio receive signal, comprising a first duplex filter and a second duplex filter, a signal divider for splitting a transmit input signal into a first transmitter signal portion and a second transmitter signal portion, the first transmitter signal portion being passed to the a transmit port of the first duplex-filter, and a second signal portion being passed to the second transmitter port of the second duplex filter. The filter arrangement further comprising a signal combiner/divider for combining a first filtered transmit portion signal and a second filtered transmit portion signal into a single filtered transmit signal. The filter arrangement further comprising a signal combiner for combining a first filtered receive signal portion and a second filtered receive signal portion into a single filtered receive signal, which is provided at a third output of the signal combiner. With such a filter arrangement the suppression of noise from the transmit signal in the receive signal is improved.

Claims

1. A filter arrangement for filtering a radio transmit signal and radio receive signal, comprising

a first duplex filter, the first duplex filter comprising a first transmitter port, a first receiver port, and a first antenna port

a second duplex filter, the second duplex filter comprising a second transmitter port, a second receiver port, and a second antenna port

a signal divider for splitting a transmit input signal into a first transmitter signal portion and a second transmitter signal portion, the first transmitter signal portion being passed to the first transmit port of the first duplex filter, and the second signal portion being passed to the second transmitter port of the second duplex filter,

a signal combiner/divider with a first signal/combiner port, connected to the first antenna port of the first duplex filter, and a second signal/combiner port, connected to the second antenna port of the second duplex-filter, the signal combiner/divider combining a first filtered transmit portion signal and a second filtered transmit portion signal into a single filtered transmit signal, which is provided at a third signal/combiner port of the signal combiner/divider, and for splitting the radio receive signal received at the third combiner/divider port into a first receive signal portion and a second receive signal portion, the first receive signal portion being provided at the first signal combiner/divider port and the second signal portion being provided at the second signal combiner/divider port

a signal combiner with a first signal combiner input, connected to the first receive port of the first duplex-filter, and with a second signal combiner port of the second duplex-filter, connected to the second receive port of the second duplex-filter, the signal combiner combining a first filtered receive signal portion and a second filtered receive signal portion into a single filtered receive signal, which is provided at a third output of the signal combiner.

2. The filter arrangement according to claim 1 wherein at least one of the signal combiner, the signal divider or the signal divider/combiner is a 90°

coupler.

3. The filter arrangement according to claim 1 wherein at least one of the first duplex filter or the first duplex filter is at least one of a ceramic filter, a surface acoustic wave filter, a bulk acoustic wave filter, a bulk acoustic resonator filter (FBAR), a cavity filter.

4. The filter arrangement according to claim 3 further providing a second amplifier, wherein the second amplifier is connected with a second amplifier output to the second transmit port of the second duplex filter.

5. The filter arrangement according to claim 4 wherein the transmitter signal splitter is a signal divider providing the first transmitter signal portion and the second transmitter signal portion, the first transmitter signal portion being passed to a first amplifier input of the first amplifier, and the second signal portion being passed to a second amplifier input of the second amplifier.

6. The filter arrangement according to claim 4, wherein the first amplifier control signal of the compensation controller is passed to a first amplifier input of the first amplifier and a second amplifier control signal of the compensation controller is passed to a second amplifier input.

7. The filter arrangement according to claim 4 wherein the transmit signal splitter is incorporated in the compensation controller and the first transmit signal portion is derived from the transmitter signal by electronically applying a 180°

phase delay to the transmitter signal and the second transmitter signal portion is derived from the transmitter signal by electronically applying a 90°

phase delay to the transmitter signal.

8. The filter arrangement according to claim 3 wherein at least one of the signal combiner, the signal divider or the signal divider/combiner is a 90°

coupler.

9. The filter arrangement according to claim 3 wherein at least one of the first duplex filter or the first duplex filter is at least one of a bulk acoustic resonator filter (FBAR), a surface acoustic wave device, a bulk acoustic wave device, a ceramic filter or a cavity filter.

3-1. A filter arrangement for filtering a radio transmit signal and a receive signal, comprising

a first duplex filter, the first duplex filter comprising a first transmitter port, a first receiver port, and a first antenna port

a second duplex filter, the second duplex filter comprising a second transmitter port, a second receiver port, and a second antenna port

a transmitter signal splitting device for splitting a transmit input signal into a first transmitter signal portion and a second transmitter signal portion,

a signal combiner/divider with a first signal/combiner port, connected to the first antenna port of the first duplex-filter, and with a second signal/combiner port, connected, to the second antenna port of the second duplex-filter, the signal combiner/divider combining a first filtered transmit portion signal and a second filtered transmit portion signal into a single filtered transmit signal, which is provided at a third signal/combiner port of the signal combiner/divider, and for splitting the radio receive signal received at the third combiner/divider port into a first receive signal portion and a second receive signal portion, the first receive signal portion being provided at the first signal combiner/divider port and the second signal portion being provided at the second signal combiner/divider port

a signal combiner with a first signal combiner input, connected to the first receive port of the first duplex-filter, and with a second signal combiner port, connected to the second receive port of the second duplex-filter, for combining a first filtered receive signal portion and a second filtered receive signal portion into a single filtered receive signal, which is provided at a third output of the signal combiner

at least a first amplifier with at least a first amplifier output connected to the first transmit port of the first duplex filter

a compensation controller providing at least a first amplifier control signal to control at least one of an amplifying gain or a phase shift, wherein the compensation controller generates the first amplifier control signal in dependence of a signal provided at a fourth divider/combiner port of the divider/combiner.

10. A method of manufacturing a filter arrangement for filtering a radio signal

connecting a first signal divider output of a signal divider to a first transmit port of a first duplex filter

connecting a second signal divider output to a second transmitter port of a second duplex filter,

connecting a first antenna port of the first duplex filter to a first signal/combiner port of a signal combiner/divider,

connecting a second antenna port of the second duplex-filter to a second signal/combiner port of the signal combiner/divider,

connecting a first signal combiner input of a signal combiner to a first receive port of the first duplex-filter,

connecting a second signal combiner port of the signal combiner to a second receive port of the second duplex-filter.

11. A computer program product comprising a non-transitory computer-usable medium having control logic stored therein for causing a computer to manufacture a filter arrangement for filtering a radio signal comprising

a first duplex filter, the first duplex filter comprising a first transmitter port, a first receiver port, and a first antenna port

a second duplex filter, the second duplex filter comprising a second transmitter port, a second receiver port, and a second antenna port

a signal divider for splitting a transmit input signal into a first transmitter signal portion and a second transmitter signal portion, the first transmitter signal portion being passed to the first transmit port of the first duplex filter, and the second signal portion being passed to the second transmitter port of the second duplex filter,

a signal combiner/divider with a first signal/combiner port, connected to the first antenna port of the first duplex filter, and a second signal/combiner port, connected to the second antenna port of the second duplex-filter, the signal combiner/divider combining a first filtered transmit portion signal and a second filtered transmit portion signal into a single filtered transmit signal, which is provided at a third signal/combiner port of the signal combiner/divider, and for splitting the radio receive signal received at the third combiner/divider port into a first receive signal portion and a second receive signal portion, the first receive signal portion being provided at the first signal combiner/divider port and the second signal portion being provided at the second signal combiner/divider port

a signal combiner with a first signal combiner input, connected to the first receive port of the first duplex-filter, and with a second signal combiner port of the second duplex-filter, connected to the second receive port of the second duplex-filter, the signal combiner combining a first filtered receive signal portion and a second filtered receive signal portion into a single filtered receive signal, which is provided at a third output of the signal combiner.