Abstract: An apparatus for improving reception sensitivity of a public wave receiver includes power devices formed in a power supply of the public wave receiver, and a shielding plate for shielding noise generated by the power devices. A signal line for connecting an antenna used for the public wave receiver to a public wave receiver main body and a ground line are formed coaxially to each other by a shield layer.

Abstract: A receiving device in which the shielding performance is improved to solve a pulling problem in a receiving device of a direct conversion system is provided.

Abstract: Briefly, in accordance with one embodiment of the invention, a portable communication device includes a microelectromechanical system (MEMS) device to couple an antennae from a first and second transceiver.

Abstract: The present invention pertains to an electrical transceiver module having a peripheral device connector to receive copper plugs having a profile equal to or larger than the outer profile of the standard module housing profile. An embodiment of the invention provides an RJ-45 receptacle as the peripheral device connector of an SFP (Small Form Factor Pluggable) transceiver.

Abstract: An RF transceiver module for wireless communication devices includes a multi-layered substrate, an RF transceiver IC mounted on the multi-layered substrate for receiving and transmitting voice or data signals, at least one band selection filter mounted on the multi-layered substrate for filtering received RF signals, an antenna switch integrated in the multi-layered substrate which can be switched to transmit RF signals generated by the power amplifiers to the external antenna or to receive RF signals from an external antenna to the RF transceiver IC through the band selection filter, a plurality of passive devices embedded in the multi-layered substrate, and wiring embedded in the multi-layered substrate for electrically connecting the passive devices, the RF transceiver IC, and the band selection filter.

Abstract: The invention relates to a radio communication device having at least one additional, current-conducting correction element connected to a printed board in the device. The correction element and printed board are configured in such a manner that a targeted, virtual current path elongation is brought about for an electric current induced on the printed board by electromagnetic radio fields of the antenna while the defined longitudinal and traverse dimensions of the printed board remain substantially unchanged.

Abstract: A system and method for providing wireless communication services to passengers of an aircraft. An incoming signal is received from a base station at an external antenna on the aircraft. The incoming signal is converted to a low-energy signal type to be conveyed across a low-energy transmission medium. The low-energy signal may be light energy and the low-energy transmission medium may be a fiber optic cable, for example. The signal is converted to a signal type that can be transmitted into the passenger compartment for reception by one or more wireless handsets. Outgoing signals transmitted by the one or more wireless handsets may also be received and converted to low-energy signals for transmission on a low-energy signal path, which may be the same as or different from the incoming signal path. The outgoing signals may then be transmitted through an external antenna on the aircraft to be received by a base station.

Abstract: The level of the harmonics of oscillation signals for synchronous detection to be inputted to a mixer circuit for converting frequencies is suppressed low.

Abstract: The invention provides a device for enhancing performance of a portable cellular phone within a mobile vehicle. The device includes a housing located within the vehicle into which a portable cellular phone may be placed. The housing includes an exterior layer that reflects noise signals and an interior layer that reduces reflection of communication signals within the housing. Signals are transmitted between the cellular phone and an exterior-mount transceiver by means of a wireless RF coupling device that is contained within the housing and connected to the exterior-mount transceiver using a coaxial cable.

Abstract: Methods and apparatus are provided for an interconnect system for coupling radio frequency signals from one component to another in a RF system. The interconnect system acts as a coaxial connection. The apparatus comprises an interconnect, a dielectric sleeve, and a conductive elastomeric gasket. The interconnect has a first major surface and second major surface for providing an electrical connection. A through hole is formed in a first component. The dielectric sleeve is placed in the through hole. The interconnect is placed in the dielectric sleeve. The conductive elastomeric gasket is placed in proximity to the through hole contacting the first component and a second component. The RF system is assembled compressing the elastomeric gasket to have intimate contact with the first and second component. The intimate contact electrically connects the first and second component and an electric shield is formed around the interconnect thereby suppressing the reception and transmission of RF signals.

Abstract: A radio frequency apparatus comprising a printed circuit board mounting an electronic component including a coil as an inductance element, a metal frame body covering this printed circuit board and connected to the ground, a lid formed integrally with the frame body, covering the inductance element mounting side of the frame body, and a leg formed by cutting and bending from the lid, having a width nearly same as the width of the coil, in which the leg is disposed closely to the coil.

Abstract: A system for wireless communications is provided. The system includes a hand-held wireless communications device, such as a cell phone. An antenna is connected to the cell phone. The antenna radiates radio waves over an area of less than 360 degrees of arc, such as in a cardioid or hemisphere. The antenna is oriented such that hemisphere is in the direction away from a head of a user of the cell phone.

Abstract: A wireless transceiver includes a circuit board, a Bluetooth module, an antenna unit and an electrical connector. The circuit board has a component mounting side to be disposed so as to confront the electronic device. The Bluetooth module and the antenna unit are mounted on the component mounting side and are connected electrically to the circuit board. The electrical connector is mounted on the circuit board and is adapted to connect electrically the wireless transceiver to the electronic device. The antenna unit has a radiating direction that is directed toward the electronic device, is adapted to cooperate with the electronic device to form a shielding space, and is adapted to form a virtual transmission source internally of the electronic device. The shielding space and the virtual transmission source cooperate to protect the wireless transceiver from interference.

Abstract: A flexible printed circuit board has first and second connection portions 18 and 19 where contacts are exposed and first and second path portions 16 and 17 where conductor patterns 11 are arranged that connect the contacts 11a and 11b of the first and second connection portions 18 and 19 together. The first and second path portions 16 and 17 are formed so as to have substantially symmetrical shapes with each other about a predetermined straight line, and the flexible printed circuit board is folded up along the straight line C1 and C2. Alternatively, a flexible printed circuit board has a conductor pattern 11 formed between first and second insulating sheets 12 and 13, and has a shielding conductor 14 fixed to the second insulating sheet 13. The flexible printed circuit board is folded up with the second insulating sheet 13 outside so that the conductor pattern 11 is enclosed inside the shielding conductor 14.

Abstract: A system for wireless communications is provided. The system includes a hand-held wireless communications device, such as a cell phone. An antenna is connected to the cell phone. The antenna radiates radio waves over an area of less than 360 degrees of arc, such as in a cardioid or hemisphere. The antenna is oriented such that hemisphere is in the direction away from a head of a user of the cell phone.

Abstract: An apparatus and method for shielding an operator from electromagnetic fields emitted from an antenna in a portable communication device. A plurality of active shields are placed between the operator's earpiece and the antenna to dampen the effects of the electromagentic fields. The active shields are coupled to adjustment circuits which may include variable gain amplifiers and phase couplers to offset the antenna signal.

Abstract: A direct conversion transceiver capable of reducing a DC offset, using a multi-chip module is provided. In the transceiver, a mixer and an element constituting a local oscillator are positioned above a shielding ground surface, and an interconnection connecting the mixer and the element constituting the local oscillator are positioned below the shielding ground surface. The transceiver is formed as a multi-chip module and thus its size is not bigger than a one-chip direct conversion receiver and advantageous in that its size and manufacturing costs are less than a general direct conversion receiver that additionally includes a DC offset cancellation circuit or an off-chip type oscillator for reducing a DC offset.

Abstract: A capacitively back-coupled wireless terminal (10) comprises a PCB (22) having a ground conductor (24) on one surface. A back coupling capacitor (C) is carried by the ground conductor. An elongate slot (30) is provided in the ground conductor to widen the bandwidth. An electromagnetic shield (32) is provided on the side of the PCB (22) which in use is facing a lossy dielectric in order to reduce the SAR. The shield is disposed adjacent to, but spaced from, the slot (30) in the ground conductor and the back coupling capacitor. For narrowband operation the slot may be omitted and/or the spacing between the PCB (22) and the shield (32) may be reduced.

Abstract: A communication apparatus including a radio frequency (RF) circuit module can be reduced in the number of components therefor to reduce the cost for its components and to simplify its fabrication process and thus reduce the cost for manufacturing the same while the RF circuit module can also be shielded reliably. The RF circuit module includes a printed circuit board having an upper surface with a circuit component mounted thereto and a lower surface provided with a shielding conductor of metal. The printed circuit board is fit into a shielding frame to assemble the RF circuit module. The RF circuit module is then turned over and thus mounted on that upper surface of a mother board which is provided with conductors of metal. Such conductors of metal and the frame can shield the RF circuit module.

Abstract: The present invention pertains to an electrical transceiver module having a peripheral device connector to receive copper plugs having a profile equal to or larger than the outer profile of the standard module housing profile. An embodiment of the invention provides an RJ-45 receptacle as the peripheral device connector of an SFP (Small Form Factor Pluggable) transceiver. An embodiment of the invention provides a receptacle outer profile being larger than the main transceiver body outer profile in at least one dimension. An embodiment of the invention provides for a transceiver having a latch member and a latching point point disposed on a main body between a first end and a second end of the housing.

Abstract: An electronic flash is provided for a body of a portable phone with a camera, and the electronic flash emits light by a release operation of a shutter release button, thereby photographing a subject by illuminating with a light. A backlight of a liquid crystal display and an electronic flash discharge tube of the electronic flash which correspond with a noise source are contained in containers which are formed on the surface of an electromagnetic shield frame, and an electronic circuit board of the portable phone with a camera is mounted on the back side of the electromagnetic shield frame, so that a shield unit is constructed. Therefore, radio waves generated from the electronic flash and the liquid crystal display are attenuated before reaching the electronic circuit board, and misoperations of the portable phone due to the radio waves can be prevented.

Abstract: The portable telephone capable of more effectively reducing the electromagnetic energy to be radiated therefrom and absorbed by the human body during its use is provided.

Abstract: The invention relates to a method of rendering telecommunication devices ineffective by creating a substantially radio frequency radiation-free environment. An interference generating pattern is provided adjacent the environment in a position between the environment and a source of radio frequency radiation signals so as to substantially reduce, or interfere with such signals thus preventing typical operation of the telecommunications devices therein. Preferably, the interference generating pattern is provided by applying silicon carbide as a coating or as part of a building material onto a structure to reduce attenuation by at least 20 to 50 decibels. Other aspects of the invention include the building materials that have the interference generating pattern associated therewith and the substantially radio frequency radiation-free environments that are created according to the methods disclosed herein.

Abstract: In a converter for satellite broadcast reception having a fixing structure provided with a circuit board, a plurality of radio-frequency circuits mounted on the circuit board and separated from one another by a grounding pattern, a chassis having ribs arranged in a pattern that corresponds to the grounding pattern, and a mount plate placed on the back surface of the circuit board, a rubber plate having resilience is placed between the circuit board and the mount plate. This permits the grounding pressure with which the grounding pattern of the circuit board is kept in contact with the chassis to be distributed uniformly, and thereby permits stable grounding to be achieved.

Abstract: In a superheterodyne receiver, energy can bypass a filter by magnetically coupling to a metallic radio frequency shield. This is especially a problem with small form factor devices in which the metallic radio frequency shield is positioned close to the filter. By using a ferrite-embedded element positioned between the filter and the RF shield, some of the undesired harmonics produced by the mixer can be dissipated into heat.

Abstract: In an electronic component (11) comprising an electronic circuit or a circuit element in a metallic case including a case (13) and a cover (39), a magnetic thin film (51) made of a magnetic loss material is provided on at least one part of an inner wall surface of the metallic case. In the magnetic loss material, its composition is represented by M-X—Y, wherein M denotes at least one of Fe, Co and Ni, X denotes at least one of elements other than M and Y, and Y denotes at least one of F, N and O. The maximum value &mgr;″max of an imaginary part &mgr;″, which is an imaginary number component of a complex permeability of the magnetic loss material, exists within a frequency range from 100 MHz to 10 GHz.

Abstract: The present invention provides a radio frequency (“RF”) shielded and acoustically isolated enclosure that efficiently employs multiple layers of sound insulation and absorbs airborne noise and the noise provided by magnetic resonance imaging (“MRI”) equipment through the supports of such equipment. The RF enclosure uses multiple layers and types of insulating materials positioned to maximize the noise absorption of the RF enclosure. This reduces the cost and space required by the enclosure. In one embodiment the enclosure includes a ceiling, a floor and a plurality of walls. The ceiling and walls include one or more multiple layers of different indulating materials that either abut each other or form air gaps. In one embodiment the floor includes a heavy metal plate on which the MRI equipment sits. The plate elastically couples to a conductive shield. The elastic coupling attenuates certain frequencies above the natural frequency of the metal sheet.

Abstract: Module for radiocommunication equipment intended to be transferred onto a motherboard and comprising components mounted on a printed circuit and ensuring at least one of the following functions: RF processing, numerical processing, and analog processing.

Abstract: A method and apparatus are disclosed for suppressing interference in a radio frequency (RF) communication system using active shielding techniques. An opposing neutralizing signal is applied to actively neutralize stray signals in a microwave communication environment. An interfering or stray signal is detected using a sensing antenna, and the opposing neutralizing signal is generated in response thereto. The opposing neutralizing signal is applied to a signal neutralizing shield to shield any desired components or devices. The opposing neutralizing signal is approximately 180 degrees out of phase, and of equal magnitude to the detected interfering signal. A phase shifter/null feedback device receives the detected stray signal, if any, and adaptively adjusts the phase and magnitude of the opposing neutralizing signal. In one embodiment, the phase shifter/null feedback device includes an integrator that generates a DC value that is proportional to the energy of the interfering signal.

Abstract: An enclosure part in the vicinity of a receiver part or an enclosure part to which a user brings its head close during a call is formed out of a nonconductive material of resin or the like, and an enclosure part being lower than the enclosure part of the nonconductive material has an electric conductor.

Abstract: Edges of the surface metal of a cage shield are bent inwardly towards an interior of a cavity formed by the cage shield to eliminate leakage at apertures in the shield. In a further embodiment, bends can also be formed by the metal layers and through holes within a printed circuit board.

Abstract: A direct conversion transceiver capable of reducing a DC offset, using a multi-chip module is provided. In the transceiver, a mixer and an element constituting a local oscillator are positioned above a shielding ground surface, and an interconnection connecting the mixer and the element constituting the local oscillator are positioned below the shielding ground surface. The transceiver is formed as a multi-chip module and thus its size is not bigger than a one-chip direct conversion receiver and advantageous in that its size and manufacturing costs are less than a general direct conversion receiver that additionally includes a DC offset cancellation circuit or an off-chip type oscillator for reducing a DC offset.

Abstract: The present invention provides a cellular phone comprising: a housing having front and rear casings wherein the rear casing comprises a metallic layer coated on an inner side of the rear casing for insulating electromagnetic radiation, a circuit board installed in the housing having a board surface and an antenna connector installed at an upper end of the board surface, an antenna installed at an upper end of the housing and electrically connected with the antenna connector at the upper end of the board surface for receiving or emitting electromagnetic radiation, and an elastic conductor.

Abstract: A case structure of the present invention having an improved EMI shielding comprises a front case, a rear case and a PCB having ground traces and a plurality of electronic components thereon, a conductive elastic member. The front and rear case are made of a metallic material. The rear case includes a bottom, a sidewall and a cavity defined between the bottom and the surrounding sidewall. The bottom forms conductive rails extending into the cavity and cooperating with the ground trace of the PCB. A conductive elastic member is formed on the rails of the rear case by applying viscous conductive resin to the rails. The ground faces of the PCB electrically connect with the conductive rails of the rear case via the conductive elastic member, thus, providing an improved shield consisting of the rear rails, the PCB, and the front rear cases. The imposed shield is simpler to assemble and lower in cost since no additional frame and screws are required.

Abstract: The present invention is directed to electronic components shielded from electromagnetic interference through the use of conforming shield enclosures. Conforming shield enclosures are flexible metalized thermoformed thin-wall polycarbonate polymer film substrates used to shield a radiation source. The present invention relates to conforming shielded forms for electronic component assemblies and specifically to electronic component assemblies which are shielded to protect against electromagnetic and radiofrequency interference. Specifically, the shielded electronic component assembly comprises (a) a semiconductor device to be shielded from electromagnetic frequencies; (b) a reference potential source; (c) a housing enclosing the semiconductor device within the assembly; and (d) a conforming shield enclosure electrically connected to the reference potential source.

Abstract: A guide rail (1) mountable onto a printed circuit board (2) for receiving a GBIC module therein includes a frame (10), a cover (12) and an electrical connector (14) fixed to the frame. The frame has two side beams (16) and a rear beam (18) connecting the side beams, and a receiving space (26) defined between the two side beams and the rear beam for receiving the GBIC module therein. The frame defines a port (22) at a front portion thereof for entrance of the GBIC module. The electrical connector has a mating portion (58) adapted for mating with the GBIC module and a mounting portion (59) adapted for mounting to the printed circuit board. The side beams each define a receiving slot (17) in an inner wall (19) thereof and the connector has a pair of ribs (60) at two opposite sides thereof. The ribs are fixedly received in the respective receiving slots, thereby retaining the connector to the guide rail.

Abstract: A portable phone includes a front portion, and a cover made of titanium material and detachably engaged onto the front portion of the portable phone for shielding the electromagnetic waves generated by the portable phone. The cover includes a latch or one or more sockets or one or more catches for engaging with the latch opening or the lock studs or the lock notches of the portable phone and for detachably securing the cover to the portable phone. The cover includes a number of orifices and a window for aligning the dial buttons and the displayer of the portable phone.

Abstract: A radio telephone, preferably intended for cellular telecommunication, has an apparatus housing (20) and at least one antenna (21), which is mounted to or in connection with the apparatus housing for performing the wireless communication of the radio telephone by transmitting and receiving radiofrequent electromagnetic waves in a given wavelength range. A current-reducing means (30, 31) is mounted to the apparatus housing (20) between the antenna (21) and a side (23) of the radio telephone, which during normal use faces a human user (1). The means has conductive as well as dielectric properties and is arranged to reduce or eliminate electric currents present in and/or on the apparatus housing (20) between the antenna (21) and said side (23) of the radio telephone.

Abstract: In a television tuner system, a printed board is disposed within a frame having a side plate. A tuner and an intermediate frequency circuit are disposed adjacent to each other on the printed board. The tuner has a mixer and a local oscillator. The intermediate frequency circuit includes at least a SAW filter having a plurality of terminals. A first ground conductor is formed between the tuner and the intermediate frequency circuit. A second ground conductor is formed at a peripheral edge of the printed board. The SAW filter is placed along the second ground conductor in such a manner that the terminals of the SAW filter are arranged substantially parallel to the side plate. The local oscillator is disposed substantially on a line extending from the arrangement of the terminals of the SAW filter. With this arrangement, the distance between the output terminals and the local oscillator is greater than that between the input terminal and the local oscillator.

Abstract: The invention relates to an arrangement for the protection of electronic functional units and/or functional groups from disturbance quantities. The invention is characterized in that a division of the functional units and/or groups into partial units and/or groups with different sensitivity to the disturbance quantities is provided, in that a different screening from the disturbance quantities is assigned to the partial units and/or groups with different sensitivity to the disturbance quantities, and in that at least two of the screenings complete each other to a screening with a greater efficiency degree or factor, respectively.

Abstract: An IC mounting structure and a communication apparatus is provided in which the structure of a circuit substrate is improved, the positional relationship between an IC and an antenna member is optimized, and the influence of high-frequency noises from the active surface of the IC can be prevented. In a wrist-fitting communication apparatus, an IC which generates high-frequency noises is face-down bonded on a circuit substrate such that the active surface faces the side opposite to the direction where most of or the entire antenna member is positioned. The circuit substrate is a multilayer substrate in which a shielding electrode layer maintained at the ground potential or a power supply potential is formed. High-frequency noises generated from the active surface of the IC are reduced by the shielding electrode layer. Also, electromagnetic field leaking to the surroundings is weak. Accordingly, the influence of noise upon the antenna member is small.

Abstract: A tuner for both digital and analog use that can receive both digital broadcast and analog broadcast signals, includes a signal input terminal; a frequency conversion section which converts and inputted signal to an IF signal; and a switching/distributing section which, based on the type of received signal (analog/digital), switches a destination to which to send the IF signal or distributes the IF signal. There is also a down-converter section, that further converts the IF signal into a Low IF signal; a terminal for output of the IF signal. The aforementioned components are all contained in a single body that performs an electromagnetic seal function. Operation of the switching/distributing section and/or the down-converter section may be controlled by a control signal from a structural element within the body.

Abstract: A vehicle surroundings monitoring device capable of performing distance measurement as desired even in a short-distance range to provide unerring alarm information to a driver. The monitoring device for monitoring surroundings around a vehicle has a transmitting antenna provided in a door mirror assembly of the vehicle to radiate transmitted waves through a mirror surface of the door mirror, and a receiving antenna provided in the door mirror assembly to receive reflected waves from an object existing near the vehicle through the door mirror surface. The monitoring device also has a stray electric wave limiting member for reducing electric wave components straying from the transmitting antenna into the receiving antenna.

Abstract: A light guide/shield assembly for use with a circuit board includes an upstanding, electrically conductive shield wall adapted to be mounted on and electrically grounded to the circuit board. The shield wall defines an opening. A light guide member including a light transmissive guide body and an electrically conductive shield layer is mounted on the shield wall such that the shield layer overlies the opening. The light guide/shield assembly thereby defines an RF shielded chamber. The light guide/shield assembly may further include an LCD panel mounted on the light guide member. An RF shielded PCB assembly includes a circuit board including an electrical ground and the light guide/shield assembly mounted thereon.

Abstract: An EMI shielded telecommunications equipment enclosure includes a metal cabinet structure and an access panel. The cabinet structure defines a compartment configured to contain electrical equipment that emits and is susceptible to EMI. An edge portion of the cabinet structure defines a peripheral boundary of an access opening for the compartment. The access panel includes a metal panel structure which overlies the edge portion of the metal cabinet structure when the access panel is closed. The apparatus further includes a layer of electrically nonconductive material which is interposed as a dielectric between the metal panel structure and the edge portion of the metal cabinet structure when the access panel is closed. In this configuration, a low capacitive impedance path for EMI shielding is provided between the access panel and the metal cabinet structure.

Abstract: There is provided a small-sized and lightweight image display apparatus which is thinned in the line of sight and which incorporates a display unit for displaying a magnified virtual image and a direct image, the display apparatus comprising a real image display part for displaying an image, an image magnifying means for optically magnifying the image formed in the real image forming means so as to form a virtual image, and a light guide means for guiding light from the real image display part to the image magnifying means, the magnifying means being formed in a triangular columnar shape having a substantially isosceles triangular cross-section, and having a first surface serving a light incident surface, a light emanating surface and a reflective surface, and a first internal reflecting surface and a second internal reflecting surface for reflecting light into the light guide means, wherein emanating light from the real image display part is incident upon the light guide means through the first surface, and

Abstract: A multilayer ceramic integrated circuit module for a receiver front-end of a wireless communication device is provided. The module contains an embedded component portion, which has a plurality of thick film capacitors; a plurality of multilayer capacitors; and a plurality of transmission lines deposited internal to the multilayer ceramic integrated circuit module to interconnect the plurality of thick film capacitors and the plurality of multilayer capacitors. The module also contains a mounted component portion, which has a pair of pin diodes; a transistor and a plurality of resistors coupled thereto, for controlling the bias of the pair of pin diodes; and a low-noise-amplifier. The module reduces the size and weight of wireless devices and combines multiple functions into a highly integrated device.

Abstract: An electromagnetic shield for a radiotelephone includes a frame and a shield insert that fits into the frame. The frame comprises a generally rectangular wall structure that forms a part of the housing for the radiotelephone. The shield insert is sized and shaped to fit into the frame and is retained in the frame by friction, interference fit, or snap features. A plurality of interchangeable shield inserts can be made to fit into a standard frame.

Abstract: A portable radio terminal comprises a housing, a radio circuit included in the housing, a matching circuit mounted on the top of the housing at a position which is offset from the longitudinal center line of the housing, a load connected to the tip of the matching circuit, and a linear antenna connected to the load. This portable radio terminal further comprises load changing means for changing the value of the load. The matching circuit may comprise a meander matching element, a zigzag-shaped matching element, a helical matching element, a conical matching element, a rectangular helical matching element or a pyramid helical matching element which are formed so as to a predetermined shape, such as a meander shape, a zigzag shape, a helical shape, a conical shape, a rectangular helical shape or pyramid helical shape.

Abstract: Since the radio wave absorbent of the present invention has the main component of a magnesium-zinc system ferrite material containing 45 to 50 mol % of iron oxide, 7 to 19.7 mol % of magnesium oxide, 24 to 28.5 mol % of zinc oxide, 4 to 16 mol % of copper oxide, and 0.1 to 6 mol % of manganese oxide, a matching thickness is less than 8 mm, and the total weight of the radio wave absorbent for use in the inner wall of a radio wave dark room or the outer wall of a building or the like is remarkably reduced as compared with the radio wave absorbent obtained by sintering the conventional magnesium-zinc system ferrite material. Moreover, since the radio wave absorbent can be obtained by sintering the material at a relatively low sintering temperature of about 950 to 1150° C., the manufacture cost can be reduced relative to the radio wave absorbent obtained by sintering the conventional nickel-zinc system ferrite material.