Tunable isolator

• US 7,265,643 B2
• Filed: 02/14/2002
• Issued: 09/04/2007
• Est. Priority Date: 04/11/2001
• Status: Expired due to Term

• Current Assignee: Kyocera Corporation
• Original Assignee: Kyocera Wireless Corporation (Kyocera Corporation)
• Inventors: Toncich, Stanley S.
• Primary Examiner(s): Jones; Stephen E.
• Application Number:
  US10/077,654
• Publication Number:
  US 20020149439A1
• Time in Patent Office: 2,028 Days
• Field of Search: 333/1.1, 333/24.2
• US Class Current: 333/24.2
• CPC Class Codes: G01R 27/2694 Measuring dielectric loss, e.g. loss angle, loss factor or power factor
• CPC Class Codes: H01G 7/06 having a dielectric selected for the variation of its permittivity with applied voltage, i.e. ferroelectric capacitors electrets H01G7/02
• CPC Class Codes: H01L 27/0808 Varactor diodes
• CPC Class Codes: H01P 1/203 Strip line filters
• CPC Class Codes: H01P 1/20336 Comb or interdigital filters
• CPC Class Codes: H01P 1/20363 Linear resonators
• CPC Class Codes: H01P 1/20381 Special shape resonators
• CPC Class Codes: H01P 1/2039 Galvanic coupling between Input/Output
• CPC Class Codes: H01P 1/2056 Comb filters or interdigital filters with metallised resonator holes in a dielectric block
• CPC Class Codes: H01P 1/213 combining or separating two or more different frequencies H01P1/215 takes precedence
• CPC Class Codes: H01P 5/04 with variable factor of coupling
• CPC Class Codes: H03B 5/04 Modifications of generator to compensate for variations in physical values, e.g. power supply, load, temperature
• CPC Class Codes: H03B 5/124 the means comprising a voltage dependent capacitance
• CPC Class Codes: H03B 5/1262 the means comprising switched elements
• CPC Class Codes: H03B 5/1293 having means for achieving a desired tuning characteristic, e.g. linearising the frequency characteristic across the tuning voltage range
• CPC Class Codes: H03B 5/1841 the frequency-determining element being a strip line resonator H03B5/1805, H03B5/1817, H03B5/1864 and H03B5/1882 take precedence
• CPC Class Codes: H03B 5/362 the amplifier being a single transistor H03B5/364 - H03B5/368 take precedence
• CPC Class Codes: H03F 1/56 Modifications of input or output impedances, not otherwise provided for
• CPC Class Codes: H03F 2200/111 the amplifier being a dual or triple band amplifier, e.g. 900 and 1800 MHz, e.g. switched or not switched, simultaneously or not
• CPC Class Codes: H03F 2200/294 the amplifier being a low noise amplifier [LNA]
• CPC Class Codes: H03F 2200/372 : Noise reduction and elimination in amplifier
• CPC Class Codes: H03F 3/191 : Tuned amplifiers H03F3/193, H03F3/195 take precedence
• CPC Class Codes: H03H 7/0123 : comprising distributed impedance elements together with lumped impedance elements
• CPC Class Codes: H03H 7/12 : Bandpass or bandstop filters with adjustable bandwidth and fixed centre frequency H03H7/09 takes precedence; automatic control of bandwidth in amplifiers H03G5/16
• CPC Class Codes: H03H 7/20 : Two-port phase shifters providing an adjustable phase shift
• CPC Class Codes: H03J 5/246 : using electronic means H03J5/244 takes precedence
• CPC Class Codes: H03L 1/022 : by indirect stabilisation, i.e. by generating an electrical correction signal which is a function of the temperature H03L1/021 takes precedence
• CPC Class Codes: H03L 7/18 : using a frequency divider or counter in the loop H03L7/20, H03L7/22 take precedence
• CPC Class Codes: H04B 1/0053 : with common antenna for more than one band
• CPC Class Codes: H04B 1/0458 : Arrangements for matching and coupling between power amplifier and antenna or between amplifying stages matching circuits in general H03H
• CPC Class Codes: H04B 1/30 : for homodyne or synchrodyne receivers demodulator circuits H03D1/22
• CPC Class Codes: H04B 1/40 : Circuits

Abstract

A tunable isolator is provided. At least one of the matching circuits for the isolator may be patterned or placed on a common substrate with the isolator. Additionally, at least one of the matching circuits includes a ferro-electric tunable component for tuning the impedance match of the matching circuit.

Claims

1. A tunable isolator circuit comprising:

an isolator formed on a substrate and having a input port, an output port and an isolation port;

an isolation port matching circuit formed on the substrate and connected to the isolation port, the isolation port matching circuit comprising a first ferro-electric (FE) tunable component and configured to provide natural impedance matching to a first component impedance of a first electrical component connected to the isolation port;

an output port matching circuit formed on the substrate and connected to the output port, the output port matching circuit comprising a second ferro-electric (FE) tunable component and configured to provide natural impedance matching to a second component impedance of a second electrical component connected to the output port; and

a input port matching circuit formed on the substrate and connected to the input port, the input port matching circuit configured to provide natural impedance matching to a third component impedance of a third electrical component connected to the input port, the input port matching circuit comprising a third ferro-electric (FE) tunable component and a micro-electrical-mechanical switch configured to connect an impedance component to the ferro-electric (FE) tunable component when activated, wherein the first ferro-electric (FE) tunable component, second ferro-electric (FE) tunable component, third ferro-electric (FE) tunable component, and the micro-electrical-mechanical switch are adjustable during operation of the tunable isolator circuit to tune a frequency of operation of the tunable isolator circuit from within a personal communications services (PCS) frequency band to within another PCS frequency band.

2. The tunable isolator circuit of claim 1, wherein at least one of the first ferro-electric (FE) tunable component, second ferro-electric (FE) tunable component, and third ferro-electric (FE) tunable component comprises ferro-electric tunable capacitor having an adjustable capacitance.

3. The tunable isolator circuit of claim 1, wherein the PCS frequency band is an India PCS frequency band including a 1900 megahertz frequency and the another PCS frequency band is a United States PCS frequency band including a 800 megahertz frequency.

4. The tunable isolator circuit of claim 1, wherein the second electrical component is an antenna and the third electronic component is a power amplifier.

5. The tunable isolator circuit of claim 4, further comprising a duplexer connected between the antenna and the output port and wherein the output matching circuit matches from about 12.5 ohms at the isolator output port to about 12.5 ohms at a duplexer input port.

6. The tunable isolator circuit of claim 1, further comprising a control line connected to at least one of the ferro-electric tunable components.

7. The tunable isolator circuit of claim 6, further comprising a control source electrically coupled to the control line and configured to transmit a control signal on the control line, the at least one of the ferro-electric tunable components responsive to the control signal during the operation of the tunable isolator circuit.

8. A tunable isolator circuit comprising:

an isolator formed on a substrate and having a input port, an output port and an isolation port;

an isolation port matching circuit formed on the substrate, and connected to the isolation port, the isolation port matching circuit comprising a first ferro-electric (FE) tunable component and configured to provide natural impedance matching to a component impedance of an electrical component connected to the isolation port;

an output port matching circuit formed on the substrate and connected to the output port, the output port matching circuit comprising a second ferro-electric (FE) tunable component and configured to provide natural impedance matching to a power amplifier impedance of a power amplifier connected to the output port;

a input port matching circuit formed on the substrate and connected to the input port, the input port matching circuit configured to provide natural impedance matching to an antenna circuit impedance of an antenna circuit connected to the input port, the input port matching circuit comprising a third ferro-electric (FE) tunable component and a micro-electrical-mechanical switch configured to connect an impedance component to the ferro-electric (FE) tunable component when activated; and

a control line connected to at least one of the matching circuits and configured to receive a control signal, wherein at least one of the first ferro-electric (FE) tunable component, second ferro-electric (FE) tunable component, third ferro-electric (FE) tunable component, and the micro-electrical-mechanical switch is responsive to the control signal during operation of the tunable isolator circuit to tune a frequency of operation of the tunable isolator circuit from within a personal communications services (PCS) frequency band to within another PCS frequency band.