Diplex Patents (Class 370/297)
  • Publication number: 20090268647
    Abstract: A high-frequency component in which a low-frequency-band transmission characteristic is not degraded even when impedance mismatching is generated by providing a SAW filter in a high-frequency-band circuit. The high-frequency component includes a diplexer having a high pass filter and a low pass filter connected in parallel to an antenna port, a high-frequency-band circuit serially connected to the high pass filter, and a low-frequency-band circuit serially connected to the low pass filter. A filter causing impedance mismatching is connected to the high-frequency-band circuit. The high pass filter includes a first series resonant circuit and a second series resonant circuit, and the resonance frequency of the first series resonant circuit is a trap frequency of a signal in the low-frequency band, and the resonance frequency of the second series resonant circuit is a trap frequency of undesired resonance generated in the transmission characteristic of the filter of the low-frequency-band side.
    Type: Application
    Filed: July 14, 2009
    Publication date: October 29, 2009
    Applicant: MURATA MANUFACTURING CO., LTD.
    Inventor: Takanori UEJIMA
  • Publication number: 20090262672
    Abstract: A call processing method and a mobile terminal are provided. The mobile terminal includes a Radio Frequency (RF) receiver including a first input terminal connected to a first incoming signal line and a second input terminal connected to a second incoming signal line, a first RF switch arranged on the first incoming signal line for switching the first incoming line between the first input terminal and an inter-switch line, a second RF switch arranged on the second incoming signal line for switching the second input terminal between the second incoming signal line and the inter-switch line, and a controller for controlling, in a data call session, the first RF switch and the second RF switch to establish a connection of the first incoming signal line and the second incoming signal line during a first period and during a second period.
    Type: Application
    Filed: February 25, 2009
    Publication date: October 22, 2009
    Applicant: SAMSUNG ELECTRONICS CO. LTD.
    Inventors: Oun Suk SIN, Sang Hyuk IM
  • Patent number: 7606184
    Abstract: A multiplexer, such as a diplexer, is delineated. The multiplexer may be employed in a communications system that may communicate in multiple frequency bands within a predefined range of frequencies, e.g., 2400 MHz-4900 MHz. The communications system may operate in a network, such as a wireless local area network, without significant interference from signals used by a cellular/mobile telephone system. The multiplexer may include multiple channels with bandpass filters that may be formed with lumped inductors and lumped capacitors. In at least one of the channels, the bandpass filter may be formed by combining at least one lowpass filter with at least one highpass filter.
    Type: Grant
    Filed: January 4, 2005
    Date of Patent: October 20, 2009
    Assignee: TDK Corporation
    Inventors: Kai Liu, Richard Kommrusch
  • Publication number: 20090207764
    Abstract: A high-frequency circuit for wireless communications selectively using a first frequency band and a second frequency band lower than the first frequency band, comprising an antenna terminal; first and second transmission terminals to which transmitting signals in the first and second frequency bands are input; first and second receiving terminals from which received signals in the first and second frequency bands are output; a diplexer circuit for branching a first-frequency-band-signal path and a second-frequency-band-signal path; a switch circuit for switching a path for a transmitting signal and a path for a received signal; a low-noise amplifier circuit disposed between the switch circuit and the second receiving terminal for amplifying a received signal in the second frequency band; and first and second filter circuits disposed between the antenna terminal and the low-noise amplifier circuit in this order from the antenna terminal, both filter circuits passing a received signal in the second frequency ba
    Type: Application
    Filed: May 8, 2007
    Publication date: August 20, 2009
    Applicant: HITACHI METALS, LTD.
    Inventors: Keisuke Fukamachi, Shigeru Kemmochi, Kazuhiro Hagiwara
  • Publication number: 20090185512
    Abstract: A high-frequency module has a configuration in which a diplexer is capable of separating the frequency bands of first and second communication systems from the frequency band of a third communication system, a first high-frequency switch is capable of separating a transmission signal of the first or second communication system from a reception signal thereof, a second high-frequency switch is capable of separating a transmission signal of the third communication system from a reception signal thereof, and a third high-frequency switch is capable of separating the reception signal of the first communication system from the reception signal of the second communication system. A reception-signal output port for the second communication system of the high-frequency module is terminated with a chip capacitor to configure the double-band high-frequency module supporting the first and third communication systems.
    Type: Application
    Filed: January 21, 2009
    Publication date: July 23, 2009
    Applicant: MURATA MANUFACTURING CO., LTD.
    Inventor: Masashi HAYAKAWA
  • Publication number: 20090141183
    Abstract: A method and apparatus is presented for actively signal splitting an RF signal. Specifically, the RF signal is frequency-separated to generate a first signal including a first set of frequencies and a second signal including a second set of frequencies. The first and second signals are independently amplified to generate first and second amplified signals, respectively. The first and second amplified signals are then combined to generate a recombined signal. The recombined signal is divided to generate first and second splitter output signals.
    Type: Application
    Filed: April 12, 2006
    Publication date: June 4, 2009
    Inventors: Clint Alan Ecoff, Michael Anthony Pugel
  • Patent number: 7539242
    Abstract: A semiconductor integrated circuit device has first and second receivers and first and second transmitters. The first receiver has a first clock data recovery (CDR) circuit, and the second receiver has a second CDR circuit. Each of these first and second CDR circuits receives serial data, recovers a clock from the received serial data, and changes the phase of the generated clock. The first transmitter has a first serializer (SER), and the second transmitter has a second SER. The first SER converts parallel data into serial data synchronized with a transmit clock or the clock generated by the first CDR circuit. The second SER converts parallel data into serial data synchronized with a transmit clock or the clock generated by the second CDR circuit.
    Type: Grant
    Filed: March 12, 2004
    Date of Patent: May 26, 2009
    Assignee: Kabushiki Kaisha Toshiba
    Inventor: Shinichi Yoshioka
  • Publication number: 20090129299
    Abstract: A multiplexing apparatus comprising at least one band pass filter, a receiver filter, and a transmitter filter is disclosed. The receiver filter, the transmitter filter and each band pass filter are communicatively coupled to a cable so that the receiver filter is configured to pass signals in a first spectral region from the cable to a first-band base transceiver station, the transmitter filter is configured to pass signals in the first spectral region from the first-band base transceiver station to the cable, and each band pass filter is configured to filter and bi-directionally pass signals in a second spectral region between the cable and at least one other base transceiver station.
    Type: Application
    Filed: November 21, 2007
    Publication date: May 21, 2009
    Applicant: ADC TELECOMMUNICATIONS, INC.
    Inventors: William C. Heuer, Yoshi Kasahara
  • Publication number: 20090080346
    Abstract: A method for point-to-point ethernet communication over point-to-multipoint shared single conductor channel topology comprises transmitting an ethernet signal upstream over the point-to-multipoint topology from one end point of the topology to the root of the topology, transmitting the ethernet signal downstream over the point-to-multipoint topology from the root of the topology to all end points of the topology, and selectively processing only at a designated end point the ethernet signal received at all end points. An ethernet system may comprise single conductor channel cabling (e.g., coaxial cabling) including a trunk line and a plurality of branch lines connecting to the trunk line at a plurality of points along the trunk line, a single root transceiver (root-PHY) connected at an end of the trunk line, and a plurality of end point transceivers (EP-PHYs), each connected to a respective one of the plurality of branch lines.
    Type: Application
    Filed: October 12, 2007
    Publication date: March 26, 2009
    Inventors: Scott Powell, Ali Abaye
  • Publication number: 20090073899
    Abstract: GPS functionality is added to a wireless communication device in an efficient and cost effective manner. Disclosed is a wireless communications device that has a common mixer constructed to be used for a GPS signal and another signal, a common IF filter constructed to be used for a GPS signal and another signal, in addition to other cost effective embodiments.
    Type: Application
    Filed: November 21, 2008
    Publication date: March 19, 2009
    Inventor: Tim Forrester
  • Publication number: 20090052358
    Abstract: A composite high-frequency component includes a transmission/reception selection switch. The transmission/reception selection switch includes a first diode disposed in series with a transmission signal line, a second diode disposed in shunt with a reception signal line. A first current route in which a direct current flows through the first diode and a second current route in which a direct current flows through the second diode are connected in parallel with each other. When a predetermined positive voltage is applied to a control terminal, a direct current flows through, in sequence, the control terminal, a resistor, an inductor, the diode, a strip line, a strip line, and a shared inductor, and a direct current also flows through, in sequence, the control terminal, the resistor), the diode, a strip line, the strip line, the strip line, and the shared inductor.
    Type: Application
    Filed: November 4, 2008
    Publication date: February 26, 2009
    Applicant: MURATA MANUFACTURING CO., LTD.
    Inventor: Takanori UEJIMA
  • Publication number: 20080205307
    Abstract: A transmitter (10) of an apparatus (1) for transmitting signals via at least two channels simultaneously is provided with a data processing system (30), a first serial branch (20) comprising a first inverse Fourier transformer (40,42), a second serial branch (21) comprising a second inverse Fourier transformer (41), a digital-to-analog converting system (50-53) and a radio system (60-63), the first and second serial branches being coupled in parallel. This transmitter (10) is backward compatible to a high extent. The radio system (60-63) either comprises a radio unit (60,61,62) per serial branch (20,21) or is located after the combiner (15-17) to save hardware. In the latter case, a component converter (90) or an upsampler/phaseshifter (100) is required in the first serial branch (20). The digital-to-analog converting system (50-53) either comprises a converters (50,51,52) per serial branch (20,21) or is located after a combiner (15-17) to save hardware.
    Type: Application
    Filed: June 8, 2005
    Publication date: August 28, 2008
    Applicant: KONINKLIJKE PHILIPS ELECTRONICS, N.V.
    Inventors: Bertrand Jacques Leonard Vandewiele, Manel Collados
  • Publication number: 20080181144
    Abstract: An RF transceiver system includes an RF transmitter that generates a transmit signal and an RF receiver that receives a received signal. A diplexer couples the transmit signal to an antenna, produces the received signal based on an inbound RF signal to the antenna, and isolates the transmit signal from the received signal. A mismatch detection module detects an impedance mismatch at the output of the RF transmitter by processing the transmit signal and the received signal and generates a mismatch feedback signal in response to an amount of detected mismatch. A processing module controls the amount of mismatch at the output of the RF transmitter in response to the mismatch feedback signal.
    Type: Application
    Filed: January 30, 2007
    Publication date: July 31, 2008
    Applicant: Broadcom Corporation, a California Corporation
    Inventor: Ahmadreza (Reza) Rofougaran
  • Publication number: 20080159187
    Abstract: An amplification circuit that enables a network amplifier to amplify multiple mobile telephone signals transmitted at different frequencies. The amplification circuit includes a first diplexer which receives a first signal having a first frequency band and a second signal having a second frequency band. The first diplexer generates a combined signal containing both the first and the second signals. The combined signal is amplified by a single low noise amplifier to generate an amplified combined signal. A second diplexer receives the amplified combined signal and separates the amplified combined signal into a first amplified signal having the first frequency band and a second amplified signal having the second frequency band. The resultant signals can then be transmitted by the network amplifier to a target destination, such as a handset or base station.
    Type: Application
    Filed: January 3, 2007
    Publication date: July 3, 2008
    Applicant: Wilson Electronics
    Inventor: V. Alan Van Buren
  • Publication number: 20080159186
    Abstract: The present invention employs hierarchical modulation to simultaneously transmit data over different modulation layers using a carrier RF signal. Each modulation layer may be of a higher or lower order than the other modulation layers. Certain embodiments of the present invention may transmit different information on the different modulation layers. Other embodiments of the present invention may use the different layers for processing different information streams.
    Type: Application
    Filed: December 30, 2006
    Publication date: July 3, 2008
    Applicant: NORTEL NETWORKS LIMITED
    Inventor: David G. Steer
  • Publication number: 20080152344
    Abstract: An ultra wideband adapter and a system including the ultra wideband adapter are disclosed. The ultra wideband adapter includes a first input to receive video from a passive optical network element, a second input to receive data from the passive optical network element, an ultra wideband modulator to modulate the received data, a diplexer to diplex the received video with the modulated ultra wideband data to provide a diplexed video, and an output to transmit the diplexed video.
    Type: Application
    Filed: February 21, 2008
    Publication date: June 26, 2008
    Applicant: SBC Knowledge Ventures, L.P.
    Inventor: David A. Deas
  • Patent number: 7263072
    Abstract: A system and method for making a band selection in a wireless communications device is provided. The available bands include a first-communication band, a second communication band, and an auxiliary band. A wideband diplexer provides a wideband path, which includes the first-communication band and the auxiliary band, and a second-communication band path. A combination duplexer couples to the wideband path, and has an auxiliary signal port, a first-band receive port, and a first-band transmit port. A standard duplexer couples to the second communication path to provide a second-band receive port and a second-band transmit port. In one example, the first communication band is the PCS band, the second communication band is the cellular band, and the auxiliary signal is a GPS satellite signal.
    Type: Grant
    Filed: April 16, 2003
    Date of Patent: August 28, 2007
    Assignee: Kyocera Wireless Corp.
    Inventor: Paul Martinez
  • Patent number: 7196595
    Abstract: A multilayer diplexer has a first I/O terminal, a second I/O terminal, an antenna terminal, a high-pass filter coupled between the antenna terminal and the second I/O terminal, and a low-pass filter coupled between the antenna terminal and the first I/O terminal. The high-pass filter has a first capacitor and a second capacitor connected in serial coupled between the antenna terminal and the second I/O terminal, a fourth capacitor coupled between the antenna terminal and the second I/O terminal, and a first inductor coupled between a connection node of the first and second capacitors and a reference ground. The low-pass filter has a second inductor coupled between the antenna terminal and the first I/O terminal, and a third and fifth capacitor connected in parallel coupled between the antenna terminal and the first I/O terminal.
    Type: Grant
    Filed: December 28, 2004
    Date of Patent: March 27, 2007
    Assignee: Darfon Electronics Corp.
    Inventors: Chieh Yu Tsai, Tsung Ta Tsai
  • Patent number: 6950410
    Abstract: Multiple circuits connected to a common terminal are switched where the frequency bands to be conducted through the circuits are close. Each circuit has an independent signal path to the common terminal which contains a filter and a device. Each device has a first and a second state. Each circuit has a first filter characteristic that passes a first frequency band and substantially blocks the second frequency band. Each circuit has a second filter characteristic which substantially blocks the first and second frequency bands when the device is in the second state, wherein the second filter characteristic is a result of the device and a filter acting in combination. As a result, the frequency multiplexer can have multiple frequency bands in a narrow frequency range connected to a common terminal with minimum signal loss.
    Type: Grant
    Filed: July 14, 2000
    Date of Patent: September 27, 2005
    Assignee: Telefonaktiebolaget LM Ericsson (publ)
    Inventor: Per-Olof Brandt
  • Publication number: 20040233860
    Abstract: Data signals from a telecommunication network are routed to a gateway which generates analog signal distributed to receivers within a customer premises. A network interface device receives digital signals from the telecommunication network. A first diplexer has a digital signal port connected to the network interface device. The first diplexer combined signal port is connected with the combined signal port of a second diplexer. The gateway receives digital signals from the second diplexer digital signal port and provides analog signals to the second diplexer analog signal port. Analog signals are then available to receivers at both the first diplexer analog signal port and the second diplexer analog signal port.
    Type: Application
    Filed: May 24, 2004
    Publication date: November 25, 2004
    Applicant: U S West, Inc.
    Inventors: Kurt A. Campbell, Bruce A. Phillips
  • Patent number: 6563801
    Abstract: The cable interface unit in accordance with the invention allows use of the same wire in one cable both for base-band transmission of data between telecommunication equipment in full duplex form and also for transmission of an operating voltage (V) from one device to another. In the transmission unit, data is transmitted through a hybrid connection (41) to a cable (23). After the hybrid connection, the operating voltage (V) is also brought to the cable with the aid of a diplexer (44). The hybrid connection separates the arriving data and conducts it to the receiver, where the data is shaped in an analog manner by correcting level distortions and thereupon in the digital signal processing a DECISION is made on what the received symbol is.
    Type: Grant
    Filed: January 26, 2000
    Date of Patent: May 13, 2003
    Assignee: Nokia Corporation
    Inventors: Jarmo Mäkinen, Ville Hämäläinen, Antti Raimovaara
  • Patent number: 6512765
    Abstract: An exchange equipment using STM able to achieve an improvement of an efficiency of use and an improvement of ease of increase of terminal cards, that is, an STM type exchange, including a time switch, for performing exchange processing of time division multiplexed data, wherein a ring highway is connected via a terminal common unit to an upstream highway and a downstream highway coupled to this time switch via a highway interface unit or directly and wherein a plurality of terminal cards are connected to this ring highway. Each terminal card is provided with an add/drop unit which drops and adds the data from and to an assigned time slot on the ring highway according to control information indicating time slot assignment information determined by the control unit and adds the data and with a card control unit which controls the add/drop unit.
    Type: Grant
    Filed: January 12, 1999
    Date of Patent: January 28, 2003
    Assignee: Fujitsu Limited
    Inventors: Yoshiharu Kato, Ryo Takajitsuko, Hidetoshi Iwasa, Kiyofumi Mitsuze
  • Publication number: 20020118651
    Abstract: Disclosed is a simplex/duplex switching system which can easily cope with a simplex configuration or a duplex configuration. The simplex/duplex switching system includes a first device for outputting a predetermined frame signal carrying a plurality of time slot signals; and multiple second devices, each of which is paired with another device having the same structure, wherein, when paired second devices serve together as a simplex device, each of the second devices alternately receives the time slot signals included in the predetermined frame signal; and wherein, when paired second devices serve together as a duplex device, both of the second devices receive all of the time slot signals included in the predetermined frame signal.
    Type: Application
    Filed: October 15, 1998
    Publication date: August 29, 2002
    Inventors: MASATAKA SAKAI, NAOSHI MIYASHITA
  • Patent number: 6275475
    Abstract: A communications system (100) has at least one TDD platform pair (130, 200) operating synchronously using a Time Division Duplex (TDD) frame structure. A TDD platform pair (130, 200) has first communications platform (124) and second communications platform (126) that are coupled (135) together. First communications platform (124) transmits first data during a first frame and receives second data during a second frame. Second communications platform (126) receives third data during the first frame and transmits fourth data during the second frame. At least one TDDSU (110) receives the first data, transmits the second data, transmits the third data, and receive the fourth data. First communications platform (124) has a first coverage area, and the second communications platform (126) has a second coverage area. A dual coverage area exists where the first coverage region overlaps the second coverage region. At least one TDDSU (110) is located within the dual coverage region.
    Type: Grant
    Filed: June 15, 1998
    Date of Patent: August 14, 2001
    Assignee: Motorola, Inc.
    Inventor: Thomas Peter Emmons, Jr.
  • Publication number: 20010004353
    Abstract: A high frequency composite component is miniaturized and included in a mobile communication apparatus. The high frequency composite component includes a diplexer, a duplexer, and a high frequency switch. The diplexer is defined by first inductors and first capacitors. The duplexer is defined by second inductors and second capacitors, and the high frequency switch is defined by a first diode and a second diode, third inductors, and third capacitors.
    Type: Application
    Filed: December 21, 2000
    Publication date: June 21, 2001
    Applicant: Murata Manufacturing Co., Ltd
    Inventors: Koji Furutani, Koji Tanaka, Takahiro Watanabe, Hidcki Muto, Takanori Uejima, Norio Nakajima
  • Patent number: 6240139
    Abstract: A repeater circuit (10) includes a decoder arrangement (34) and an encoder arrangement (33). The decoder arrangement (34) is connected to an input transmission line to receive an input encoded signal comprising a signal at one of four encoded voltage levels. Each of the four possible encoded voltage levels represents a different combination of first and second digital data signals. The decoder arrangement (34) decodes the input encoded signal to produce the first and second data signals. These first and second data signals then serve as inputs to the encoder (33) which encodes the signals into an output encoded signal. The output encoded signal comprises a signal similar to the input encoded signal but restored to account for parasitic resistance associated with the input transmission line (21).
    Type: Grant
    Filed: July 30, 1998
    Date of Patent: May 29, 2001
    Assignee: International Business Machines Corporation
    Inventors: Tai Ahn Cao, Satyajit Dutta, Donna W. Luk
  • Patent number: 6185434
    Abstract: A dual mode radio apparatus has an integrated filtering part (51) which includes an antenna port (51a) for connection to an antenna (21), at least one port (51b, 51c, 51d) for connection to each of the system-specific radio-frequency parts (54, 55) of the dual mode radio apparatus and filtering means for directing the propagation of signals between ports on the basis of the signal frequency. The integrated filtering part replaces earlier separate filters and their impedance matching circuits as well as some of the required radio-frequency switches.
    Type: Grant
    Filed: September 11, 1997
    Date of Patent: February 6, 2001
    Assignee: LK-Products OY
    Inventors: Panu Hagström, Seppo Yrjölä
  • Patent number: 6072363
    Abstract: A facility (VOR) is disclosed for combining and amplifying two broadband signals which are received from different transmission networks (NET1, NET2) and are transmitted in transmission channels separated in frequency. The facility (VOR) contains a broadband amplifier (BV), a preamplifier (VV), and a frequency filter unit (FW). The preamplifier (VV) and the frequency filter unit (FW) condition the signals to be amplified and establish an optimized signal-to-noise ratio between the two combined broadband signals: The preamplifier adapts the level of one of the signals to the level of the other signal, e.g., to the same value, whereby a linear and increased amplification is achieved in the broadband amplifier, and the filtering of the signals in the frequency filter unit prevents interfering signals, e.g., noise, contained in said one signal from getting into the frequency band occupied by the other signal and vice versa when the two signals are combined.
    Type: Grant
    Filed: October 27, 1998
    Date of Patent: June 6, 2000
    Assignee: Alcatel
    Inventors: Ulrich Steigenberger, Volker Hagele
  • Patent number: 6060961
    Abstract: An apparatus and associated method of manufacture for coupling a receiver and a transmitter to a single antenna feed horn so as to allow for the simultaneous transmission and reception of co-polarized signals, such as in a radio frequency communications system, are provided. To separate the two co-polarized signals of different frequencies, the apparatus comprises a waveguide junction, a first filter tuned to the transmit signal frequency, and a second filter tuned to the receive signal frequency. The apparatus may be manufactured using low-cost reusable-mandrel casting techniques.
    Type: Grant
    Filed: September 4, 1998
    Date of Patent: May 9, 2000
    Assignee: Prodelin Corporation
    Inventors: Hamid Moheb, Colin Michael Robinson
  • Patent number: 5901151
    Abstract: A high frequency signal and a low frequency signal are coupled onto a pair of conductors providing a communication link between two computer components. The high frequency signal may be a differentially coupled Fibre Channel 8B/10B encoded signal. A diplexer includes a low pass filter for attenuating the Fibre Channel signal and a high pass filter for separately attenuating the low frequency signal. A two-way communication link may be provided over twinax cable. An environmental monitor may be in connection with the low frequency communication path.
    Type: Grant
    Filed: February 13, 1997
    Date of Patent: May 4, 1999
    Assignee: Data General Corporation
    Inventors: Scott J. Bleiweiss, Thomas B. Hawkins, James W. Espy
  • Patent number: 5864584
    Abstract: The present invention allows for the simultaneous transmission of two digital signals from one integrated circuit to another. The two digital signals are encoded utilizing a voltage divider circuit and are then transmitted by one transmission line to the second integrated circuit chip. The second integrated circuit chip decodes the first digital signal and then utilizes this decoded digital signal to further decode the second digital signal.
    Type: Grant
    Filed: February 13, 1995
    Date of Patent: January 26, 1999
    Assignee: International Business Machines Corporation
    Inventors: Tai Cao, Satyajit Dutta, Thai Quoc Nguyen, Thanh Doan Trinh, Lloyd Andre Walls
  • Patent number: 5802187
    Abstract: Disclosed is a programmable sound generator for generating digital outputs of tone and noise signals used for producing computer sound effects. The programmable sound generator includes at least two channels generating digital output serving as either tone signal or noise signal. A mixer is used to process the outputs of the channels in a digital, time-sharing manner. A volume controller coupled to the mixer is used to control the volume of the sound in a digital pulse width modulation (PWM) manner. Also, the volume controller allows its output to become floating when the programmable sound generator is not in use so as to allow another sound generating means to share the same sound transducing means. In the programmable sound generator, the tone generation and the noise generation share the same hardware, which allows low-cost production of the programmable sound generator.
    Type: Grant
    Filed: January 26, 1996
    Date of Patent: September 1, 1998
    Assignee: United Microelectronics Corp.
    Inventor: Jerry Hsu
  • Patent number: 5742897
    Abstract: A dual-band radio receiver utilizes a single transformer to provide impedance matching between signal mixers from separate signal paths to their respective intermediate frequency filters. Thus, a dual-band radio receiver can be made eliminating one transformer and the printed circuit board space of one transformer. In addition, only one transformer needs to be frequency aligned or adjusted during manufacturing.
    Type: Grant
    Filed: November 6, 1995
    Date of Patent: April 21, 1998
    Assignee: Ford Global Technologies, Inc.
    Inventors: Robert Donald Plowdrey, Robert Carl Beier, Yao Hsien Kuo
  • Patent number: 5673292
    Abstract: A radio-frequency broadcasting system and method for simultaneously broadcasting analog and digital signals in a standard AM broadcasting channel wherein the system includes: a transmitter for providing, and broadcasting, a composite signal containing an adaptively-modulated phase-shift-keyed digital signal with analog programming material modulated thereon; and a receiver for detecting the composite signal, extracting the analog audio signal and digital audio, or data, therefrom, and playing back the received audio programming. The adaptively-modulated phase-shift-keyed digital signal is responsive to the transmitted signal, dynamically increasing the digital data transmission rate as the transmitted signal power increases. Symbol states are generally arranged around concentric arcs, and adjacent symbol states are generally equidistant.
    Type: Grant
    Filed: September 20, 1996
    Date of Patent: September 30, 1997
    Assignee: Northrop Grumman Corporation
    Inventor: Barry W. Carlin
  • Patent number: 5604747
    Abstract: A modular, multi-channel, contiguous output, multiplexer which combines directional filters with the diplexed output of two multi-channel multiplexers, each covering a contiguous frequency band, i.e., one is a low multiplexer and the other a high multiplexer, and one or more quasi-elliptical directional filters after the diplexer output to cover the hole left by the diplexer crossover. A preferred embodiment may essentially consist of: 1) a 12 channel contiguous multiplexer, either a hybrid directional and manifold type multiplexer or a short circuited multiplexer, covering frequencies, e.g., in the range from 3.7 GHz to 4.2 GHz; 2) a 6 channel contiguous multiplexer spanning frequencies substantially in the range from 3.42 GHz to 3.62 GHz; 3) a diplexer including a 6 section Chebyshev filter, with a passband of frequencies, e.g., in the range of 3.4 to 3.620 GHz, and about 30 dB attenuation at 3.7 GHz, and an 8 section Chebyshev filter passing frequencies, e.g., in the range of 3.7 GHz to 4.
    Type: Grant
    Filed: February 28, 1996
    Date of Patent: February 18, 1997
    Assignee: Hughes Electronics
    Inventor: Michael C. Callas