Abstract: An active waveguide transition includes a waveguide defining a waveguide volume and including a back short wall at a first end. A first probe is mounted on the waveguide in an operable position extending into the waveguide volume, and a first RF electrical signal connector is mounted on the active waveguide transition. A first circuit assembly is mechanically coupled to an exterior surface of the waveguide, the circuit assembly including a first multi-layer ceramic substrate with an RF amplifier system mounted thereon. The RF amplifier system is electrically coupled to the multi-layer ceramic substrate, the first probe, and the first RF electrical signal connector to define an active first signal path for RF communication signals between the probe and first RF signal connector.

Abstract: A radar sensor that includes a circuit board, a waveguide structure having at least one waveguide channel, and at least one pin that is pressed into the circuit board. The pin connects the circuit board to the at least one waveguide channel of the waveguide structure in such a way that radar signals may be coupled into the at least one waveguide channel and/or decoupled from the at least one waveguide channel.

Abstract: A directional waveguide coupler (20) has four input ports and four output ports. Each input port is coupled to each of the output ports. The directional coupler (20) includes a first coupler having two waveguides (W1, W2) coupled to each other by a first slot array (S1), defined in a first wall (21) common to the two waveguides (W1, W2) of the first coupler. A second coupler has two waveguides (W3, W4), coupled to each other by a second slot array (S2), defined in a second wall (22) common to the two waveguides (W3, W4) of the second coupler. The first and second slot arrays (S1, S2) lie on a first common plane. The first and second couplers are coupled to each other by a third slot array (S3) and a fourth slot array (S4), which lie on a second common plane perpendicular to the first common plane.

Abstract: The specification describes systems, and operation thereof, allowing parents or other parties to monitor mobile device activities of a child. In addition, parent can dynamically control mobile device activities of the child. Software, or network adjuncts, can link a mobile device to a station set or mobile phone under the control of the parent. Calling traffic to and from the mobile device may be routed to a receiver at a location monitored by the parent. In some embodiments, software allows the parent to intervene in the communications of the child. The intervention may take a variety of forms, such as interrupting a call in progress, terminating call activity, interrupting or terminating Internet access. Where the mobile device is provided with pre-programmed restraining software, the intervention may be modifying the restraining software.

Abstract: Techniques for communicating with a user on a network include receiving acceleration data that indicates acceleration of a mobile network node associated with a user of a network. A communication state for the user is determined based at least in part on the acceleration data. The communication state indicates a type of network communication suitable for communicating with the user. Network communications with the user are based on the communication state. Among other uses, such techniques allow a network communicating with a human through a mobile node carried by the human to infer from stopped or unusual motions when the human's ability to receive or act on communications is impaired or otherwise affected.

Abstract: A signal coupler for coupling wireless signals out of and into a waveguide system is described. The signal coupler includes an input output connector, an outer conductor coupled to the input output connector, and a radiator section, wherein the radiator section is configured to rotate about a center axis of the outer conductor. A wireless distribution system, including a waveguide with a hollow cross-sectional structure and a signal coupling device, is also described. A wireless distribution system, including a waveguide with a hollow cross-sectional structure and a plurality of signal coupling devices, is also described. A method of operating a wireless distribution system is also described. The method includes providing a wireless distribution system and inserting a first group of wireless signals in a preselected bandwidth into the waveguide.

Abstract: A radio frequency communications network system and protocol for allowing the dissemination of data to be shared by devices within a network. The invention is particularly useful when the devices are out of transmission range of each other. The network includes repeater devices located between the devices to manage a data transfer in the network. The invention also provides for data transfer management in the presence of collisions between conflicting data transmissions.

Abstract: Methods, apparatuses, and systems directed to facilitating troubleshooting wireless connectivity issues in a wireless network. In accordance with one embodiment of the present invention, either a diagnostic supplicant in the wireless client or a diagnostic manager initiates a troubleshooting protocol between the diagnostic supplicant and the diagnostic manager over a diagnostic link in response to one or more events. In one embodiment, after the diagnostic supplicant establishes a link to a diagnostic manager via a diagnostic link, the diagnostic supplicant generates and transmits a problem report to the diagnostic manager. The problem report initiates a troubleshooting protocol between the diagnostic manager and the diagnostic supplicant.

Abstract: The present disclosure relates to a system and method for selecting a network for use by a communication device to process a data transmission. In the method, the following actions are conducted: tracking transmission characteristics of networks used by the device; maintaining a set of options for the device relating to the networks, including at least one option based on the transmission characteristics; utilizing a selected option identify a selected network to process the data transmission by the communication device; and processing the data transmission using the selected network.

Abstract: A communications terminal is provided, which includes a reading device which reads in access information recorded on a prescribed recording medium, the access information being necessary for acquiring content which can be played back by a playback device from a prescribed server via a network; and a playback control device which controls the playback device and the reading device. The playback control device controls receiving the content and metadata from the server, and playing back the content according to the metadata, if the content corresponding to the read access information is not stored in the storage device when the reading device reads in the access information; and the playback control device controls playing back the content stored in the storage device according to the metadata stored in the storage device in association with the content, if the content corresponding to the read access information is stored in the storage device.

Abstract: Systems and methods for signalling transitions between talk-spurt state and silence state for wireless terminals having semi-persistently allocated uplink resources are employed. A layer 1/2 indication of the state transitions may be transmitted using a resource that is specifically allocated for that purpose. Alternatively, ACK/NACK signalling may be employed. Layer 1 indications may be employed for both state transition types. Alternatively, in-band MAC layer signalling may be used to signal state transition from talk-spurt state to silence, or the network may deduce this state transition on its own. A different uplink wireless transition resource is allocated for the talk-spurt state vs. the silence state.

Abstract: An integrated circuit (IC) includes a die and a package substrate. The die includes circuit modules and an RF bus transceiver module and the package substrate includes a micro-electromechanical (MEM) area. The RF bus transceiver module includes a baseband processing module, a transmitter section, a receiver section, a transformer, an impedance matching circuit, and a transmission line. At least one of the transformer, the impedance matching circuit, and the transmission line is within the MEM area.

Abstract: A radio transceiver device includes circuitry for radiating electromagnetic signals at a very high radio frequency both through space, as well as through wave guides that are formed within a substrate material. In one embodiment, the substrate comprises a dielectric substrate formed within a board, for example, a printed circuit board. In another embodiment of the invention, the wave guide is formed within a die of an integrated circuit radio transceiver. A plurality of transceivers with different functionality is defined. Substrate transceivers are operable to transmit through the wave guides, while local transceivers are operable to produce very short range wireless transmissions through space. A third and final transceiver is a typical wireless transceiver for communication with remote (non-local to the device) transceivers.

Abstract: A direct conversion multi-band TV tuner includes: a plurality of RF (radio frequency) paths for processing the RF signal and for generating a plurality of processed RF signals, respectively; and a TSC (tri-state chopper) based quadrature frequency converter for receiving one of said processed RF signals and converting the received processed RF signal into a in-phase baseband signal and a quadrature baseband signals; wherein the TSC based quadrature frequency converter operates in accordance with a first set of periodic three-state control signals and a second set of periodic three-state control signals that are approximately 90 degrees offset from the first set of periodic three-state control signals.

Abstract: Systems and methodologies are described that facilitate dynamically scheduling frequency sets for reuse by user devices to reduce inter-cell interference by evaluating an overall scheduling metric for each user device in a wireless communication region. The overall scheduling metric can be evaluated by determining a fairness metric for each user device in a wireless communication region, an overall channel peak desirability metric for each user device, and a channel delay desirability metric for each user device. The overall scheduling metric can be the product of the fairness metric and one or more of the overall channel peak desirability metric and the channel delay desirability metric. A user device with a highest overall scheduling metric score for a given round of dynamic scheduling can be awarded a frequency set.

Abstract: An RF interconnection between RF Printed Wiring Boards (PWBs) includes a waveguide transmission line coupled between the RF PWBs. The waveguide feeds are provided as integral parts of each PWB. In one embodiment, the waveguide interconnecting the PWBs is provided as an integral part of a support structure which supports the PWBs. By providing the interconnecting waveguide and the feeds at each end of the waveguide as integral pieces of other already existing structures, a reliable, low cost RF interconnection between RF PWBs having relatively few separate pieces is provided.

Abstract: A method and an arrangement for testing a radio device without radiation losses are provided. The arrangement comprises a waveguide closed at both its ends and comprising a holder arranged to hold the radio device at least partly inside the waveguide in such a manner that the radiating part of the radio device remaining outside the waveguide is entirely inside the holder. The arrangement also comprises at least one coupling inside the waveguide for transmission and reception of a radio-frequency signal.

Abstract: A time division duplexing (TDD) transmission/reception apparatus and method are provided. The TDD transmission/reception apparatus includes: a transmitter which generates a transmitted signal; an antenna which transmits the transmitted signal to an external device and receives a received signal from an external device; a receiver which restores source data by demodulating the received signal; and a polarized duplexer which has a first end connected to the transmitter and the receiver and a second end connected to the antenna and comprises an inclined surface, the inclined surface polarizing the transmitted signal and the received signal such that the directivity of the transmitted signal and the directivity of the received signal are perpendicular to each other.

Abstract: Systems and techniques are disclosed relating to communications. The systems and techniques involve supporting communications between a base station and a plurality of users by establishing an overhead channel between one of the users and the base station, and transmitting data from said one of the users to the base station on the overhead channel in response to a message having a threshold value related to a loading on the base station by the users. It is emphasized that this abstract is provided to comply with the rules requiring an abstract which will allow a searcher or other reader to quickly ascertain the subject matter of the technical disclosure. It is submitted with the understanding that it will not be used to interpret or limit the scope or the meaning of the claims.

Abstract: The home agent system of the present invention performs not only the process of managing the position information of a mobile node, but also the process of transferring a packet to the mobile node using the position information. The home agent system comprises one or more position processing devices processing the position information notification packet transmitted from the mobile node and acquiring the position information of the mobile node and a transfer processing device transferring the packet addressed to the mobile node, which is connected to one or more position processing devices. The transfer processing device has a position information management table which stores the position information acquired by the position processing device in association with the home address of the mobile node and a transfer unit transferring the packet addressed to the mobile node using the stored position information.

Abstract: Described are a method and a device for high speed transmission of a data signal across an electrical interconnect in an integrated circuit. An optical carrier is modulated with a local oscillator signal at a modulation frequency substantially greater than the data signal to generate an optical local oscillator signal. Phototransducers at the ends of the interconnect illuminated by the optical local oscillator signal generate electrical local oscillator signals. At the transmit end of the interconnect, the data signal is mixed with an electrical local oscillator signal to generate an upconverted data signal. After transmission across the interconnect to the receive end, the upconverted data signal is mixed with the electrical local oscillator signal to retrieve the original data signal.

Abstract: A method and system for providing location based services (LBSs) to a mobile-subscriber terminal (MST) roaming in a serving network is provided. A location based service provider (LBSP) that is outside of the serving network receives from the serving system an MST-initiated request for LBSs and an identifier of a first location system (LS1) that is associated with the serving network. Responsive to the MST-initiated request, the LBSP sends to a second location system (LS2) (i) a request for mobile positioning information (MPI) for the MST, and (ii) the identifier. Using the identifier, the LS2 addresses and sends the request for MPI to the LS1. Responsively, the LS1 populates a shared database with the MPI. The LS2 retrieves the MPI from the shared database and sends it to the LBSP. The LBSP sends to the MST a reply to the MST-initiated request for LBSs.

Abstract: A doubly balanced upconverter mixer includes a local oscillator balun circuit comprising juxtaposed foil elements on opposite sides of an insulated substrate with electrical interconnections between the foil elements. An IF balun circuit also comprises series tuned and parallel tuned foil elements on opposite sides of the substrate in juxtaposition to each other. A diode switching network interconnects the baluns. A local oscillator signal is connected to the foil elements of the local oscillator balun circuit, an RF signal is coupled to one foil element of the IF balun circuit and an IF signal is taken from the other foil element of the IF balun circuit. Another embodiment incorporates MESFET type switches, the gates of which are supplied directly with a symmetrical local oscillator signal. This arrangement eliminates the need for the local oscillator balun.

Abstract: A pulse modulator includes a circulator which comprises: two ferrite plates; a plurality of mode suppressors for transmitting therethrough an LSM mode electromagnetic wave while shutting off an LSE mode electromagnetic wave; and an impedance matching member mounted on one end face of each of the mode suppressors, wherein a pulse modulation switch having a Schottky barrier diode is mounted on the other end face of any one of the mode suppressors in such a manner that the direction of application of a bias voltage to the Schottky barrier diode coincides with the direction of electric field of the LSM mode electromagnetic wave, and wherein the distance from an edge of the ferrite plates to the Schottky barrier diode is set approximately equal to n?/2. Herein, n is an integer not smaller than 1, and ? is the wavelength of the high frequency signal.

Abstract: An electronic (or computer) apparatus (10) has a current position data output unit (13) and an area data output unit (14) responsive to current position data from the current position data output unit for producing specific country data representative of a specific country including a current position. A wireless LAN connecting unit (12) is preliminarily given a plurality of wireless LAN communication modes corresponding to a plurality of country data. Upon reception of the specific country data, the wireless LAN connecting unit automatically sets, as a selected communication mode, one of the wireless LAN communication modes which corresponds to the specific country data and carries out transmission/reception via a wireless LAN (11) in the selected communication mode. Each of the wireless LAN communication modes is determined by a radio frequency channel and a transmit power level used in a country represented by the country data.

Abstract: A double balanced mixer consisting of an RF balun, a local oscillator balun and a diode “quad” bridge circuit connected between the two baluns and where the IF output is taken at the center tap of the RF balun secondary transformer. A second harmonic termination consisting of an RLC resonant circuit is coupled across the diode bridge at the RF side. Each arm of the diode bridge, moreover, includes three series connected diodes. The mixer is in the form of a microminiature integrated circuit (MMIC) using HBT emitter-based junction diodes fabricated on a gallium arsenide (GaAs) substrate.

Abstract: In a router or packet processing node supporting Mobile IP, a method for causing packets to be retransmitted from a sender to a mobile node is disclosed. A plurality of packets having associated update information are received. The packets are intended for the mobile node. The update information associated with at least one of the received packets is stored. When the mobile node is disconnected from the sender and reconnects to the sender, without waiting for a timeout the sender is directed to retransmit a last portion of packets to the mobile node based on the stored update information. Apparatus and computer readable medium embodiments are also disclosed.

Abstract: A line coupling structure for coupling a dielectric waveguide to a suspended line has the dielectric waveguide including dielectric strips and two conductor plates that are approximately parallel to each other, the dielectric strips and a circuit board being sandwiched between the conductor plates. The line coupling structure also has the suspended line including the conductor plates and a conductor pattern on the circuit board. The conductor pattern is arranged in a direction that is substantially perpendicular to the dielectric strips. A protruding conductor pattern that extends in the extending direction of the dielectric strips is provided at a crossing position of the conductor pattern and the dielectric strips.

Abstract: Disclosed is a NRD waveguide mixer adopting a ring hybrid coupler applicable to a small-sized and high functional millimeter wave receiving/transmitting device. The NRD waveguide has a housing including two parallel conductive plates. The ring hybrid coupler is installed in the housing and has an annular ring formed with first to fourth ports which are radially extended about the annular ring. An oscillating device is connected to the first port so as to generate a local oscillating signal. A rod antenna is connected to the second port so as to receive/transmit a radio frequency signal. A first balanced mixer mount is connected to the third port and is provided with a first Schottky diode. A second balanced mixer mount is connected to the fourth port and is provided with a second Schottky diode. The radio frequency signal and the oscillating signal inputted from the first and second ports are mixed in the ring hybrid coupler to be transformed into an addition signal and a subtraction signal.

Abstract: A NRD guide includes a pair of parallel plate conductors opposed to each other at a spacing equal to or shorter than half the wavelength of a high-frequency signal to be transmitted and having opposing inner surfaces whose arithmetic average roughness Ra satisfies 0.1 &mgr;m≦Ra≦50 &mgr;m, and a dielectric strip arranged between the pair of parallel plate conductors and held in contact with the respective inner surfaces of the parallel plate conductors. The dielectric strip is strongly secured to the inner surfaces to exhibit an excellent durability. The transmission loss of the high-frequency signal can be effectively suppressed.

Abstract: A mixer having a diode quad, and which receives two RF signals at an RF input balun having primary and secondary windings. A resonant circuit arrangement includes at least a capacitor circuit element in parallel with the secondary winding to form an open circuit termination for the second harmonics of the input RF signals.

Abstract: In a transmission line assembly, a dielectric plate has a continuous protruding portion on at least one of the surfaces thereof so as to form a convex section, electrodes are formed on both of the surfaces of the dielectric plate including the outer surface of the protruding portion, and a plurality of through holes, each electrically interconnecting the electrodes formed on both of the surfaces of the dielectric plate, is arrayed on each side along the protruding portion. Accordingly, the space surrounded by the electrodes and the arrayed through holes operates as a transmission line in a mode equivalent to TE10 mode.

Abstract: The present invention comprises apparatus, methods and articles of manufacture for wireless communication networks. A mobile communication device includes a geographic drive, which is used to upload and/or download files from the network. Uploading and downloading of files occurs through a connection point, and thus the transfer of files can be controlled throughout the network.

Abstract: A mixer converts input power at high-frequency RF into output power at a different and much lower frequency IF, with the assistance of another high-frequency oscillator (LO). Typically, a very low IF frequency requires an LO that approximates the RF frequency. However, a subharmonic mixer facilitates low IF with LO frequencies significantly lower than the RF frequency. This balanced odd-subharmonic mixer consists primarily of a four-port BALUN and a pair of diodes. The diodes terminate two ports of the BALUN connecting in series and in anti-parallel to the remaining external BALUN ports. The external BALUN ports constitute the RF and the LO high-frequency mixer ports. The mixer's lower-frequency IF port also connects to the diodes, comprising a separate channel that is co-linear with one BALUN external port, and coupling capacitively to the other. All three mixer ports meet at a mixing chamber (part of the BALUN) where the diodes are located.

Abstract: In a satellite broadcasting converter, converting portions project from an inner face portion of a horn section, and therefore, the inner face of a waveguide section, the inner face portion of the horn section, and the converting portions can be formed by using a single mold. This reduces the number of molds, compared with the conventional converter, and thereby achieves a low-cost satellite broadcasting converter.

Abstract: The following description regards a frequency converter (1) for applications on millimetric radio waves. The circuit structure comprises a diplexer filter realized in thin film on an alumina layer connected to a balun set up by a quartz plate on which two mixing diodes in GaAs have been mounted, placed in the center of a rectangular cavity (2) closed on one side by a short circuit plate and on the opposite side communicating with a rectangular waveguide (4) transporting a radio frequency signal (RF). On the upper side of the plate three parallel metallic bands have been put in the sense of the width of the cavity, between the bands the diodes are connected in series. The most external bands are welded to the walls of the cavity (2), the central one on the other hand is connected to the point common to both sections of the diplexing filter by means of a metallic strap in the air welded to a microstrip.

Abstract: A diode circuit in a dielectric waveguide device designed to improve the facility with which a circuit substrate is mounted in the dielectric waveguide, to make matching between a dielectric waveguide and a diode easier, and to reduce conversion losses, and a detector and a mixer using such a diode circuit. A conductor pattern is disposed so as to intersect a pair of dielectric strips substantially perpendicularly to the same, and two filter circuits are formed in the dielectric pattern on opposite sides of the dielectric strips, thereby forming a resonance circuit. A diode is mounted in the resonance circuit in series with the conductor pattern.

Abstract: An arrangement is provided for combining the video and audio signals from a satellite antenna with other auxiliary input signals producing a frequency stacked band arrangement for transmission by a single cable to a satellite receiver or TV monitor located within a home or structure. Multiple TV input signals from the satellite antenna are processed and separated into intermediate frequency bands which are then combined in a diplexer with one or more auxiliary input frequency bands. The output of the diplexer is connected directly to the signal output terminal at the antenna. All components for performing this combining process are included within the sealed housing of the LNB provided at the satellite antenna. Improved band isolation and reduced noise and interference are produced by the novel arrangement.

Abstract: In a microwave transmission system a microwave signal is transmitted by a transmitter (1) using an antenna (2) to a receiver (4) which employs an antenna (3). The received signal is coupled to a mixer (17) via a waveguide section (15) having a cut off frequency being higher than the frequency of the signal generated by the local oscillator unit (18). In this way undesired emission of local oscillator signal is avoided. Furthermore no additional image rejection filter is required.

Abstract: The invention concerns a millimeter wave mixer realized by windowing, and includes a coplanar conductive line (320) that is produced in plating (212) on a substrate (211) disposed in a rectangular waveguide. The coplanar line (320) divides the plating (212) into two parts. The coplanar line (320) is guided out along the narrow sides of the waveguide and is connected to each of the two parts of the plating (212) via first and second diodes (41, 42). At least two slot lines (51-54) are produced parallel to the broad sides of the waveguides in the plating (212).

Abstract: A non-radiative dielectric waveguide mixer includes at least one conductive plate, a dielectric waveguide held on said conductive plate and a solid-state device disposed across said dielectric waveguide for mixing at least two high-frequency signals which are propagated in opposite directions along said dielectric waveguide. The non-radiative dielectric waveguide mixer may be combined with a high-frequency signal generator and an antenna mechanism to provide a non-radiative dielectric waveguide radar module.

Abstract: A microwave mixer is formed of three orthogonally oriented waveguides, each having a rectangular cross-section defined by a pair of opposed broad walls and a pair of opposed sidewalls wherein the ratio of cross-sectional dimensions typically is 2 :1. The mixer includes an input coupling probe, a mixing region, and an output filter disposed serially along a first of the waveguides. A second of the waveguides applies a reference LO signal via the probe to the mixing region, the mixing region including at least one diode with two diodes being employed in the preferred embodiment of the invention. A section of dielectric board serves to support the diodes of the mixing region, components of the filter, and the probe in the first waveguide.

Abstract: A microwave integrated apparatus, particularly useful for a satellite broadcasting receiver, comprises a housing having a radiation aperture and being electromagnetically shielded except for the radiation aperture. An insulated substrate is disposed in the housing, and has formed thereon an antenna pattern capable of receiving or radiating microwaves through the radiation aperture of the housing. A signal-processing means is disposed beside the insulated substrate in the housing, and is connected to the antenna pattern on the insulated substrate. For achieving a microwave circuit arrangement having excellent performance characteristic of a very wide frequency range, a second antenna pattern is disposed at the radiation aperture of the housing, and in proximity to the above-mentioned antenna pattern.

Abstract: A passive uniplanar double-balanced RF mixing apparatus, comprising a planar support substrate with first and second conductive layers disposed on first and second sides, and first and second linear slotlines having open terminations on a first end thereof formed in the first conductive layer. First and second coplanar waveguides are also formed in the first conductive layer with each having one end electrically coupled to first and of said first and second slotlines, respectively. A first balun comprises the first coplanar waveguide connection to the first slotline, and a second balun comprises the second coplanar waveguide connection the second slotline. An isolation gap formed in the first conductive layer adjacent to and between the first and second slotlines provided electrical isolation between the first and second baluns and waveguides for RF-toLO isolation.

Abstract: A millimeter wave device having a dielectric substrate with a pair of substantially parallel planar surfaces with at least one predetermined millimeter wave circuit pattern formed in a conductive layer located on at least one of the substrate surfaces. A substantially planar conductive channel plate is mounted adjacent the conductive layer on one substrate surface with the channel plate having an aperture overlying each circuit pattern formed in the conductive layer. A substantially planar conductive cover plate is mounted adjacent one of the channel plates so as to form a first cavity in the region defined by the substrate surface, the channel plate aperture and the cover plate. The device may further include a second substantially planar conductive channel plate mounted adjacent the other one of the substrate surfaces with the second channel plate having an aperture corresponding to and aligned with the first channel plate aperture.

Abstract: An electromagnetic dispersive delay line (10) includes a dielectric strip (28) as well as a coupler (24, 34, 36, and 38) for launching surface electromagnetic waves into the dielectric strip. The upper surface of the dielectric strip (28) is left exposed to the air in order to provide an interface with a lower-permittivity medium of propagation. This permits a surface-electromagnetic-wave propagation mode. The thickness of the dielectric strip (28) is varied along its length so as to result in a linear relationship of delay to frequency throughout a predetermined frequency range. Preferably, a conductive strip (26) spaced from the dielectric strip extends along the surface-wave propagation path in the region occupied by the evanescent field external to the dielectric strip (28). This conductive strip (26) modifies the phase relationships between the electric and magnetic fields in the evanescent-field region so as to cause some of the power transmission to occur outside of the dielectric strip.

Abstract: A microwave converter comprises circuit components formed on the outer surfaces of a three-dimensional body. The inner surfaces of the body constitute a grounding surface. A local oscillator is disposed on one of the inner surfaces. The three-dimensional body may be an electrically conductive body having a hollow space in which the local oscillator is disposed.

Abstract: A subharmonic mixer is shown to comprise two pairs of matched antiparallel GaAs diodes disposed on a dielectric slab and operative with microstrip circuitry. By suppressing the fundamental mixing products, mixing the radio frequency signal with the second harmonic of a local oscillator (LO) signal and using relative phase differences of the LO signals in the two pairs of diodes, undesirable effects from spurious signals are minimized.

Abstract: A low noise microwave amplifier wherein a length of a pair of broad or wider walls inside the rectangular waveguide is shortened at least near a portion where a probe for introducing a microwave signal into the amplifying portion is provided. A cutoff frequency of the waveguide near the portion where the probe is provided is raised and comes to 80% to 90% of the lower limit of the frequency of the desired amplification band of the amplifier. An input microwave having a frequency component below the cutoff frequency is prevented from flowing into the amplifier, whereby the generation of oscillation is effectively prevented.

Abstract: A combined duplexer/mixer especially for use in an FMCW millimetric radar system has a waveguide section containing a fin line or suspended strip structure for responding to the linearly polarized radar return signal passing through the section in one direction while permitting passage of the orthogonally polarized, outgoing signal passing in the other direction. The fin line is coupled via double balanced mixer diodes to an IF output line to produce an IF signal by mixing the return signal with a portion of the outgoing signal tapped off by a field distorting probe, ridge section or like coupling means.