Patents by Inventor John David Rhodes
John David Rhodes has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).
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Patent number: 11342644Abstract: A microwave resonator comprising a hollow tube comprising an electrically conductive tube wall which defines a tube bore, the tube extending along a length axis from a first end to a second end; a first electrically conductive closing plate closing the first end of the tube, the first electrically conductive closing plate comprising at least one coupling slot extending therethrough; a second electrically conducting closing plate closing the second end of the tube, the second electrically conductive closing plate comprising at least one coupling slot extending therethrough; a plurality of dielectric resonant pucks, each puck comprising first and second end faces and a side wall extending therebetween, each puck being dimensioned such that when in the tube its dominant mode is a doubly degenerate mode; the pucks being arranged within the tube bore spaced apart from each other and the closing plates, each puck being arranged centered on the length axis and its side wall abutting the tube wall such that there isType: GrantFiled: February 28, 2019Date of Patent: May 24, 2022Assignee: ISOTEK MICROWAVE LIMITEDInventors: John David Rhodes, David Ibbetson, Vanessa Walker, Christopher Ian Mobbs
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Patent number: 11239537Abstract: A microwave resonator comprising a hollow tube comprising fan electrically conductive tube wall which defines a tube bore, the tube extending along a length axis from a first end to a second end; a first electrically conductive closing plate closing the first end of the tube; a second electrically conductive closing plate closing the second end of the tube; a plurality of dielectric resonant pucks, each puck comprising first and second end faces and a side wall extending therebetween, each puck being dimensioned such that its dominant mode is a doubly degenerate mode; the pucks being arranged within the tube bore spaced apart from each other and the closing plates, each puck being arranged with its end faces normal to the length axis and centered on the length axis and its side wall abutting the tube wall such that there is no air gap between the puck and tube wall which extends from one end face to the other of the puck, the puck adjacent to the first closing plate being termed the input puck; each puck beinType: GrantFiled: February 13, 2018Date of Patent: February 1, 2022Assignee: ISOTEK MICROWAVE LIMITEDInventors: John David Rhodes, David Ibbetson, Vanessa Walker, Christopher Ian Mobbs
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Patent number: 11056755Abstract: A microwave resonator comprising a hollow tube comprising a plurality of electrically conductive wall faces which together define a tube wall defining a tube bore, the tube extending along a length axis from a first end to a second end; the tube wall having an N fold rotational symmetry about the length axis where 2<N<10; a first electrically conductive covering plate covering the first end of the tube; a second electrically conductive covering plate covering the second end of the tube; a dielectric puck comprising first and second end faces and a side wall extending therebetween, the puck being dimensioned such that when in the tube bore its dominant resonant mode is a doubly degenerate mode; the puck being arranged in the tube bore spaced apart from the covering plates with its end faces normal to the length axis and centered on the length axis; the puck being spaced apart from the tube wall by a plurality N of electrically conductive spacer blocks, the spacer blocks being spaced equally around the leType: GrantFiled: February 13, 2018Date of Patent: July 6, 2021Assignee: ISOTEK MICROWAVE LIMITEDInventors: John David Rhodes, David Ibbetson, Vanessa Walker, Christopher Ian Mobbs
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Publication number: 20210043994Abstract: A microwave resonator comprising a hollow tube comprising an electrically conductive tube wall which defines a tube bore, the tube extending along a length axis from a first end to a second end; a first electrically conductive closing plate closing the first end of the tube, the first electrically conductive closing plate comprising at least one coupling slot extending therethrough; a second electrically conducting closing plate closing the second end of the tube, the second electrically conductive closing plate comprising at least one coupling slot extending therethrough; a plurality of dielectric resonant pucks, each puck comprising first and second end faces and a side wall extending therebetween, each puck being dimensioned such that when in the tube its dominant mode is a doubly degenerate mode; the pucks being arranged within the tube bore spaced apart from each other and the closing plates, each puck being arranged centered on the length axis and its side wall abutting the tube wall such that there isType: ApplicationFiled: February 28, 2019Publication date: February 11, 2021Applicant: ISOTEK MICROWAVE LIMITEDInventors: John David Rhodes, David Ibbetson, Vanessa Walker, Christopher Ian Mobbs
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Publication number: 20200052360Abstract: A microwave resonator comprising a hollow tube comprising a plurality of electrically conductive wall faces which together define a tube wall defining a tube bore, the tube extending along a length axis from a first end to a second end; the tube wall having an N fold rotational symmetry about the length axis where 2<N<10; a first electrically conductive covering plate covering the first end of the tube; a second electrically conductive covering plate covering the second end of the tube; a dielectric puck comprising first and second end faces and a side wall extending therebetween, the puck being dimensioned such that when in the tube bore its dominant resonant mode is a doubly degenerate mode; the puck being arranged in the tube bore spaced apart from the covering plates with its end faces normal to the length axis and centered on the length axis; the puck being spaced apart from the tube wall by a plurality N of electrically conductive spacer blocks, the spacer blocks being spaced equally around the leType: ApplicationFiled: February 13, 2018Publication date: February 13, 2020Applicant: ISOTEK MICROWAVE LIMITEDInventors: John David Rhodes, David Ibbetson, Vanessa Walker, Christopher Ian Mobbs
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Publication number: 20190386365Abstract: A microwave resonator comprising a hollow tube comprising fan electrically conductive tube wall which defines a tube bore, the tube extending along a length axis from a first end to a second end; a first electrically conductive closing plate closing the first end of the tube; a second electrically conductive closing plate closing the second end of the tube; a plurality of dielectric resonant pucks, each puck comprising first and second end faces and a side wall extending therebetween, each puck being dimensioned such that its dominant mode is a doubly degenerate mode; the pucks being arranged within the tube bore spaced apart from each other and the closing plates, each puck being arranged with its end faces normal to the length axis and centered on the length axis and its side wall abutting the tube wall such that there is no air gap between the puck and tube wall which extends from one end face to the other of the puck, the puck adjacent to the first closing plate being termed the input puck; each puck beinType: ApplicationFiled: February 13, 2018Publication date: December 19, 2019Applicant: ISOTEK MICROWAVE LIMITEDInventors: John David Rhodes, David Ibbetson, Vanessa Walker, Christopher Ian Mobbs
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Patent number: 9147922Abstract: An electrical filter for filtering an electrical signal, the filter having a transmission characteristic comprising a band edge at a band edge transition frequency, the filter comprising a circulator having a first circulator port for receiving a signal to be filtered, the circulator being adapted to transfer a signal received at the first circulator port to a second circulator port and being further adapted to transfer a signal received at the second circulator port to a third circulator port; and, a reflection mode filter connected to the second port; the reflection mode filter comprising a filter network comprising at least one resonator, the filter network having a network input connected to the second circulator port; and, a further resonator connected to the network input, the further resonator being arranged to provide an extracted pole providing a transmission zero closest to the band edge transition frequency; wherein the further resonator has a high Q compared to the low Q of at least one of the atType: GrantFiled: January 5, 2011Date of Patent: September 29, 2015Assignee: FILTRONIC WIRELESS LIMITEDInventors: John David Rhodes, Christopher Mobbs
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Patent number: 9077064Abstract: According to one or more embodiments, a directional filter assembly (10) comprises a multi-port filter circuit (12) for combining or separating signals in specified pass-bands and an isolated port (20) having a resistive load (22), for absorbing out-of-band signals. The assembly further includes a reflective protection device (24) configured to protect the resistive load (22) from being overpowered by out-of-band signal power, based on being configured to reflect or not reflect the out-of-band signals in dependence on the level of out-of-band signal power. In at least one embodiment, the directional filter assembly is configured as a microwave transmission assembly, such as is used for combining signals from two or more base stations, for transmission from a common antennae assembly.Type: GrantFiled: November 23, 2010Date of Patent: July 7, 2015Assignee: Telefonaktiebolaget L M Ericsson (publ)Inventors: Bosse Franzon, Jan-Erik Lundberg, Rune Johansson, Torbjörn Lindh, Claudia Muñiz Garcia, John David Rhodes
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Patent number: 8704620Abstract: A linear actuator includes a drive arm and an extension arm each extending along a common drive axis. One of the arms has a plurality of resiliently deformable fingers extending beyond the end of the arm towards the other arm. At least one of the fingers has a thread on its inner face while the other arm has a threaded portion. At least part of the threaded portion is received between the fingers. The fingers are adapted to urge the threads of the two arms into interengagement such that rotation of the drive arm about the drive axis displaces the extension arm along the drive axis. The two threads are arranged such that when the ridge of one thread is received in the groove of the other thread the two sides of the ridge abut the two edges of the mouth of the groove.Type: GrantFiled: April 9, 2009Date of Patent: April 22, 2014Assignee: Filtronic Wireless LtdInventors: John David Rhodes, Christopher Ian Mobbs, Andrew James Panks
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Patent number: 8686808Abstract: A band combining filter for filtering a microwave signal having at least one band edge at a band edge transition frequency. The filter comprises a plurality of filter sections. Each filter section comprising 3dB hybrid couplers having input ports and output ports and resonators connected between the input ports and the output ports of the couplers. The filter sections are connected in cascade such that the outputs of one filter section are connected to the inputs of the next filter section in the cascade. A subset of the filter sections are high Q filter sections with the Q values of the resonators of those filter sections having values each of which are at least a factor of three higher than the Q values of the resonators of the remaining filter sections.Type: GrantFiled: June 1, 2011Date of Patent: April 1, 2014Assignee: Filtronic Wireless LtdInventor: John David Rhodes
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Patent number: 8554277Abstract: A microwave transmission assembly comprising a combiner comprising first and second input ports and internal and external output a ports; the combiner being adapted to transfer a signal received at microwave frequency f1 at the first input port to the external output port and signals received at other frequencies to the internal output port; the combiner being further adapted to transfer a signal at a microwave frequency f2 at the second input port to the external output port and signals received at the other frequencies to the internal output port; a resistive load connected to the internal output port; and, a power dependent reflective load connected in series with the resistive load, the power dependent reflective load comprising a reactive element, the reactive element comprising an inductive component and a capacitive component and being adapted to resonate at a load frequency; the impedance of the capacitive component being adapted to drop when the incident microwave power received by the power dependenType: GrantFiled: November 23, 2010Date of Patent: October 8, 2013Assignee: Filtronic Wireless LimitedInventors: Bosse Franzon, Jan-Erik Lundeberg, Rune Johansson, Torbjorn Lindh, Claudia Muniz Garcia, John David Rhodes
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Publication number: 20120309458Abstract: A microwave transmission assembly comprising a combiner comprising first and second input ports and internal and external output a ports; the combiner being adapted to transfer a signal received at microwave frequency f1 at the first input port to the external output port and signals received at other frequencies to the internal output port; the combiner being further adapted to transfer a signal at a microwave frequency f2 at the second input port to the external output port and signals received at the other frequencies to the internal output port; a resistive load connected to the internal output port; and, a power dependent reflective load connected in series with the resistive load, the power dependent reflective load comprising a reactive element, the reactive element comprising an inductive component and a capacitive component and being adapted to resonate at a load frequency; the impedance of the capacitive component being adapted to drop when the incident microwave power received by the power dependenType: ApplicationFiled: November 23, 2010Publication date: December 6, 2012Inventors: Bosse Franzon, Jan-Erik Lundeberg, Rune Johansson, Torbjorn Lindh, Claudia Muniz Garcia, John David Rhodes
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Publication number: 20120306596Abstract: A microwave filter for filtering a microwave signal is disclosed. The microwave filter has at least one band edge at a band edge transition frequency. The filter comprises an input port and an output port. The filter also comprises a plurality of single resonators connected in parallel between the input and output ports. The filter further comprises a frequency independent electrical coupling between the input and output ports connected in parallel with the resonators. A subset of the resonators has Q values each of which are at least a factor of three higher than the Qs of each of the remaining resonators.Type: ApplicationFiled: June 1, 2011Publication date: December 6, 2012Applicant: ISOTEK ELECTRONICS LIMITEDInventor: John David Rhodes
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Publication number: 20120306590Abstract: A band combining filter for filtering a microwave signal having at least one band edge at a band edge transition frequency. The filter comprises a plurality of filter sections. Each filter section comprising 3dB hybrid couplers having input ports and output ports and resonators connected between the input ports and the output ports of the couplers. The filter sections are connected in cascade such that the outputs of one filter section are connected to the inputs of the next filter section in the cascade. A subset of the filter sections are high Q filter sections with the Q values of the resonators of those filter sections having values each of which are at least a factor of three higher than the Q values of the resonators of the remaining filter sections.Type: ApplicationFiled: June 1, 2011Publication date: December 6, 2012Applicant: ISOTEK ELECTRONICS LIMITEDInventor: John David Rhodes
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Publication number: 20120293275Abstract: An electrical filter for filtering an electrical signal, the filter having a transmission characteristic comprising a band edge at a band edge transition frequency, the filter comprising a circulator having a first circulator port for receiving a signal to be filtered, the circulator being adapted to transfer a signal received at the first circulator port to a second circulator port and being further adapted to transfer a signal received at the second circulator port to a third circulator port; and, a reflection mode filter connected to the second port; the reflection mode filter comprising a filter network comprising at least one resonator, the filter network having a network input connected to the second circulator port; and, a further resonator connected to the network input, the further resonator being arranged to provide an extracted pole providing a transmission zero closest to the band edge transition frequency; wherein the further resonator has a high Q compared to the low Q of at least one of the atType: ApplicationFiled: January 5, 2011Publication date: November 22, 2012Inventors: John David Rhodes, Christopher Mobbs
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Publication number: 20120229229Abstract: According to one or more embodiments, a directional filter assembly (10) comprises a multi-port filter circuit (12) for combining or separating signals in specified pass-bands and an isolated port (20) having a resistive load (22), for absorbing out-of-band signals. The assembly further includes a reflective protection device (24) configured to protect the resistive load (22) from being overpowered by out-of-band signal power, based on being configured to reflect or not reflect the out-of-band signals in dependence on the level of out-of-band signal power. In at least one embodiment, the directional filter assembly is configured as a microwave transmission assembly, such as is used for combining signals from two or more base stations, for transmission from a common antennae assembly.Type: ApplicationFiled: November 23, 2010Publication date: September 13, 2012Applicant: TELEFONAKTIEBOLAGET LM ERICSSON (PUBL)Inventors: Bosse Franzon, Jan-Erik Lundberg, Rune Johansson, Torbjörn Lindh, Claudia Muñiz Garcia, John David Rhodes
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Patent number: 8228135Abstract: A band combining filter for passing signals in a communications band includes a plurality of cascaded directional filters. Each directional filter has at least two inputs and at least two outputs. The nth directional filter is arranged such that output signals O1 and O2 from the first and second outputs are related to input signals I1, I2 to the first and second inputs by the relation ( O 1 O 2 ) = ( R n ? ? 1 T n ? ? 2 T n ? ? 1 R n ? ? 2 ) ? ( I 1 I 2 ) with R and T being reflection and transmission functions respectively. The directional filters are connected in a cascade with the first and second inputs of the nth directional filter being connected to the first and second outputs of the (n?1)th directional filter respectively in the cascade. At least one of the reflection functions Rn overlaps with the corresponding reflection function Rn?1 within the communication band but is different thereto.Type: GrantFiled: February 23, 2009Date of Patent: July 24, 2012Assignee: Filtronic Wireless LtdInventor: John David Rhodes
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Publication number: 20110115577Abstract: A linear actuator includes a drive arm and an extension arm each extending along a common drive axis. One of the arms has a plurality of resiliently deformable fingers extending beyond the end of the arm towards the other arm. At least one of the fingers has a thread on its inner face while the other arm has a threaded portion. At least part of the threaded portion is received between the fingers. The fingers are adapted to urge the threads of the two arms into interengagement such that rotation of the drive arm about the drive axis displaces the extension arm along the drive axis. The two threads are arranged such that when the ridge of one thread is received in the groove of the other thread the two sides of the ridge abut the two edges of the mouth of the groove.Type: ApplicationFiled: April 9, 2009Publication date: May 19, 2011Inventors: John David Rhodes, Christopher Ian Mobbs, Andrew James Panks
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Patent number: 7915977Abstract: A tuneable bandpass filter includes a plurality of coupled resonators. A common structure of the filter includes at least one common coupling or one common resonator. An upper loop includes first and second end resonators coupled together by a signal path and further includes at least one further signal path extending between end resonators. The further signal path includes at least one further resonator with the end resonators being coupled to the common structure. A lower loop includes first and second end resonators coupled together by a signal path and further includes at least one further signal path extending between end resonators. The further signal path includes at least one further resonator with the end resonators being coupled to the common structure.Type: GrantFiled: September 19, 2007Date of Patent: March 29, 2011Assignee: Isotek Electronics LimitedInventors: John David Rhodes, Christopher Ian Mobbs, David Ibbetson
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Publication number: 20110001585Abstract: A tuneable filter comprising a filter body defining a tuning cavity; a tuning member within the tuning cavity; and, a linear actuator adapted to displace the tuning member within the cavity to tune the filter; the linear actuator comprising a motor; a drive arm connected to the motor and extending along a drive axis, the drive arm being adapted to be rotated about the drive axis by the motor; an extension arm extending along the drive axis being connected at one end to the tuning member and being in engagement with the drive arm at the other end; the engagement between the drive arm and extension arm being arranged such that rotation of the drive arm about the drive axis displaces the extension arm along the drive axis; each of the drive arm and extension arm comprising an end stop, the end stops being arranged such that as the extension arm reaches the end of its range of travel towards the drive arm the drive arm end stop rotates into abutment with the extension arm end stop, preventing further rotation ofType: ApplicationFiled: August 5, 2008Publication date: January 6, 2011Inventors: John David Rhodes, Andrew James Panks, Christopher Ian Mobbs