Abstract: A method and system wherein a system gateway (18) determines, from closed loop power control information, a power density at an antenna (13a) of a user terminal 13. The gateway also maintains a record of a duration of time that the power density exceeds a specified threshold. The gateway determines if an averaged transmitted power density associated with the antenna of the user terminal will equal or exceed at least one of a predetermined threshold level, within a specified period of time, or an absolute threshold level. If the gateway determines that a threshold will probably be exceeded if the call connection is maintained, the gateway terminates the connection prior to a time that the user terminal averaged transmitted power density level equals or exceeds the predetermined or absolute threshold level. A tone or a visual indicator may be employed to warn the user that a current connection or call will be terminated. Provisions are made for allowing predetermined types of calls (e.g.

Abstract: Apparatus, and an associated method, facilitates maintenance of ambient temperature levels within a radio base station cabinet above a minimum temperature level. During periods of low activity at a radio base station, signals are applied to a power amplifier of the transmitter portion of the radio base station. Thermal energy is generated as a byproduct of amplification of the signals provided thereto. The signals are selected such that the signals are rejected by filter circuitry, such as the duplexer filter circuitry, of the radio base station. Thereby, thermal energy is generated but amplified signals are prevented from being transmitted by the radio base station.

Abstract: The present invention relates to a novel use of cryoelectronic equipment to implement an extremely sensitive and stable receiver front end for UHF, microwave, and millimeter wave applications. The invention is particularly applicable to base station receivers in mobile radio systems, where the range and capacity of the systems are typically limited by the base station receiver sensitivity.

Abstract: In a radio communication apparatus, a switch circuit is connected between a transmitter and first and second antennas. A control circuit is connected to the first antenna and the switch circuit and controls the switch circuit in accordance with a standing wave ratio measured from the first antenna. That is, when the standing wave ratio of the first antenna exceeds a predetermined value, the connection between the transmitter and the first antenna is switched to the connection between the transmitter and the second antenna.

Abstract: An electronic circuit (200) for a portable electronic device includes an energy source interface (202), a load (204) coupled to the energy source interface (202), an energy storage circuit (206) having a maximum operating voltage, and a switch circuit (208). The switch circuit (208) is coupled to the energy source interface (202) in series with the energy storage circuit (206). The switch circuit (208) operates to switchably decouple the energy storage circuit (206) in response to a voltage at the load (204) that exceeds the maximum operating voltage.

Abstract: A processor monitors the real time forward link power utilization in a base station, and a controller regulates the real time forward link power utilization in the base station. The processor and controller operate in a feedback configuration to maintain call quality and prevent damage to the base station. The processor determines real time forward link power utilization on a per frame basis by taking samples at a per chip rate within each frame. The forward link power is then obtained by taking the mean of the samples.

Abstract: A method and apparatus for reducing the amount of heat generated by a base station is disclosed. The method includes measuring the temperature of the base station equipment with a temperature sensor. When the sensor detects that a first predefined temperature level is reached, a first alarm in the mobile switching center is triggered. In response, the mobile switching center blocks a first predefined number of transceivers. Similarly, if the temperature continues to rise past a second and third predefined temperature levels, the mobile switching center blocks a second and third respective predefined number of transceivers as necessary. As the temperature decreases, the mobile switching center unblocks the respective transceivers in reverse order as determined by the temperature. The technique reduces the operating temperature of the base station such that equipment failure due to excessive heat is prevented.

Abstract: A device for radio communication (PH), such as for example radiophone, a shielding layer (RFS) which under operating conditions is between the antenna means and the user. The shielding layer (RFS) reduces electromagnetic irradiation of the user. The shielding layer (RFS) may be movable in such a manner that it serves as a cover of some operational device such as for example headphone, display and keyboard of apparatus when it is not in use.

Abstract: A shielding device for use with a communications device, the shielding device comprising an electrically conductive element, a support for slidably supporting the conductive element, a mount to mount the support in position relative to the communication device and a slider to slide the electrically conductive element from a retracted position to an extended position, the electrically conductive element, when in the extended position, having a predetermined position relative to the antenna of the communication device.

Abstract: A carrier and shield arrangement, where the transceiver of a circuit board is exchangeable through the front panel of a station in the computer network. The shield physically connects to the carrier mounted on the circuit board, where the carrier receives the transceiver and electrically connects the transceiver to the circuitry on the circuit board. The shield has two walls, a cover and a panel portion which are formed of a material to block electromagnetic interference. The walls are electrically connectable to the circuit board, and a panel portion of the shield is electrically connectable to the carrier and to the front panel.

Abstract: An automatic transmission power control circuit which can detect an abnormality in a transmission power without a comparing circuit which compares a detected voltage with reference voltages. A detector detects a voltage corresponding to the transmission power and outputs a detected voltage. A comparator compares the detected voltage with a reference voltage so that the transmission power is controlled based on an output of the comparator. A transmission power abnormality detecting circuit includes a counter which cumulates the output of the comparator. The transmission power abnormality detecting circuit outputs a transmission power abnormality detection signal when an output of the counter is a value which is out of a normal range when the automatic power transmission control circuit is normally functioning.

Abstract: The invention relates to portable mobile communication device. The system according to the invention measures the power transmitted by the mobile communication device and the reflected power returning from the antenna. From these, the system calculates various parameters, for example, the short-term average value, the cumulative sum of transmitted power used during a call and the proportion of power reflected back. The user may set the limit values which he requires for these parameters, and the system will issue an alarm when these are exceeded. If the user so desires, the system may also continuously display the value of a desired quantity. With the aid of the system according to this invention, the user may monitor the benefit of different positions and ways in which the appliance is used and the power consumption of the mobile communication device in different situations, and thus avoid unfavorable operating situations and methods.

Abstract: An apparatus, method and article of manufacture are disclosed which provides for auxiliary battery conservation in adapters requiring auxiliary batteries. A power controller selects from one of two or more power sources to provide variable power components with DC power. For instance, power consumption of the transmitter (more specifically the transmit power amplifier) varies with the desired transmit power level. The transmitter can be supplied with DC power from the host device or the auxiliary source or both. The power controller can select the source of DC power (i.e., the host device or the auxiliary battery) or may combine the two power sources to provide necessary power to the transmit power amplifier.

Abstract: An accessory for a mobile communication device such as a mobile telephone (1) comprises a shield (12) adapted to provide an attenuating effect to radiation from the mobile communication device (1), and means (11) to mount the shield on the device so that, in use, the shield is located between the antenna on the device and a person using the device. The shield (12) may form part of a case (11) for a communication device such as a mobile telephone.

Abstract: It is an object of the present invention to provide a portable terminal which reduces an antenna standing-wave ratio and absorbs reflected waves without inserting an isolator so that a stable operation can be obtained efficiently with a compact, low-price body.

Abstract: At least the power portion of the transmitter and the front end of the receiver of a base station of a wireless communication system are advantageously co-located with the antenna (or antennae), typically atop a tower or other elevated feature. Such co-location however exposes the electronics to lightning damage. This is avoided by placement of the electronics and antenna into lightning protection apparatus that is transparent to rf radiation during lightning-quiescent conditions but is a Faraday cage during a lightning strike, reverting to the transparent condition at the conclusion of the strike. This is achieved by placement of the electronics and antenna inside a housing that comprises a dielectric chamber filled with ionizable gas in contact with electrodes selected such that, during a lightning strike, current can flow between the electrodes.

Abstract: In a preferred embodiment, a gain control circuit employs variable gain circuitry and a variable frequency converter, both controlled by a processor. The processor controls the carrier frequency of an RF modulated output signal of the circuit by controlling the frequency converter. The processor also preferably controls the gain of the variable gain circuitry as a function of both the output carrier frequency and temperature, as measured by a temperature sensing element. Preferably, the gain is controlled to maintain a constant gain over specified operating frequency and temperature ranges. The gain control circuit can be employed within a transceiver of a wireless communication terminal. Similar gain control circuitry can be utilized within a base station transceiver in which frequency channels are dynamically allocable among a plurality of gain-controlled amplification circuits.

Abstract: Cross-over modulation between radio frequency circuits and audio circuits is minimized in a wireless portable transceiver by locating all audio circuitry in a first section of the portable transceiver and all radio frequency circuitry in a second, separate section of the portable transceiver. In view of modality considerations in small portable transceivers, an audio signal is either radiated or received in the vicinity of the radio frequency circuitry. Isolation of the audio signal is achieved by routing this signal while in its acoustic form. Since audio signals in an electrical form are not routed around or near the radio frequency circuitry, cross-over modulation does not occur between the radio frequency circuitry and the audio circuitry.

Abstract: A fail-safe signal transmitting apparatus including a power supply which does not let a transmission output signal generate an error that would allow a dangerous situation to arise even when a multiple failure has occurred in circuits constituting the signal transmitting apparatus. In particular, the present invention includes a source failure monitoring function and in order to monitor the power supply, a fail-safe window comparator and a fail-safe ON delay circuit are employed. An output signal constituted of the logical product of source monitoring signal and a signal to be transmitted and a carrier signal is used as a transmission signal.

Abstract: A power amp module protecting apparatus of a mobile wireless phone having: a power supply unit for supplying driving power to a power amp module; a switching unit, connected between the power supply unit and an overcurrent detector, for performing a switching action in accordance with a logic level of a switching control signal output from a controller and a logic level of an overcurrent detecting signal from the overcurrent detector; the overcurrent detector, connected between the switching unit and the power amp module, for outputting an overcurrent detecting signal having a high logic level in response to the detection of an overcurrent from the power supply unit; and the controller for outputting the switching control signal to switch on the switching unit when no overcurrent is detected, for maintaining the switching unit in an off state in response continued receipt of the overcurrent detecting signal of high logic level output from the overcurrent detector and outputting the switching control signal to

Abstract: A method and apparatus are disclosed that mitigate the induction of baseband interference that can from time-division radios (e.g., radios that radiate an RF signal with a time-varying power envelope). A radio comprising an embodiment of the present invention radiates, in transmit mode, an information-bearing signal. In some or all idle modes, the radio radiates at least one energy-reducing pulse, but in an idle-mode channel. These energy-reducing pulses reduce the energy in the fundamental frequency component of the average RF power envelope of the radio and also reduce the energy in the harmonics of the fundamental frequency.

Abstract: A radiocommunication device wherein a signal pattern generated from an antenna is attenuated in a direction of a user of the device. A conducting surface is positioned proximate the antenna at a location designed to provide this attenuation.

Abstract: A method and system wherein a system gateway (18) determines, from closed loop power control information, a power density at an antenna (13a) of a user terminal 13. The gateway also maintains a record of a duration of time that the power density exceeds a specified threshold. The gateway determines if an averaged transmitted power density associated with the antenna of the user terminal will equal or exceed at least one of a predetermined threshold level, within a specified period of time, or an absolute threshold level. If the gateway determines that a threshold will probably be exceeded if the call connection is maintained, the gateway terminates the connection prior to a time that the user terminal averaged transmitted power density level equals or exceeds the predetermined or absolute threshold level. A tone or a visual indicator may be employed to warn the user that a current connection or call will be terminated. Provisions are made for allowing predetermined types of calls (e.g.

Abstract: A device for radio communication (PH), such as for example radiophone, includes a shielding layer (RFS) which under operating conditions is between the antenna and the user. The shielding layer (RFS) reduces electromagnetic irradiation of the user. The shielding layer (RFS) may be movable in such a manner that it serves a cover of some operational device such as for example the headphone, display and keyboard of the apparatus when it is not use.

Abstract: An assembly for attenuating and diverting electromagnetic, radio frequency and microwave-radiation emitted from cellular and marine band telephones, which includes a completely lined EMI/RF and microwave radiation shielded protective case to fully enclose a cellular or marine band telephone, the case including at least two telescoping parts slidably connected to each other to permit insertion or extraction of a telephone, wherein an opening is formed in one of the at least two telescoping parts to permit operating the telephone inserted therein, and a shielded section formed in one of the at least two telescoping parts thereby preventing a base of the antenna from touching a users head during use; a telescoping antenna with a connector base adapted to engage antenna circuitry of a telephone; and a removable handle attached to the outside of the shielded case, the removable handle being configured and dimensioned to permit telescoping of the case and holding of the parts together for security and comfort.

Abstract: The present invention discloses a portable telephone which is free from overheat of power amplifier module and also capable of a stable transmission even in the condition that it is unable to amplify the power enough. The portable telephone incorporates a power amplifier module which contains power FET's for amplifying transmission signals. A supply voltage monitoring means detects a supply voltage of a power supply. A control-voltage setting table stores a plurality of commands to set a control-voltage of the power amplifier module. A control-voltage selecting means selects a relevant command out of the control-voltage setting table with reference to the detected supply voltage. A control-voltage control means controls the control-voltage of the power amplifier module according to the command selected by the control-voltage selecting means. The control-voltage will be thereby reduced when the supply voltage is high.

Abstract: A radio communication device that performs time-sharing communication by switching between reception and transmission, comprises a circulator for guiding transmission signals to the antenna and reception signals from the antenna to the reception circuit. The output on the reception circuit side of the circulator is grounded via a terminal circuit which is operated during transmission and turned off during reception.

Abstract: An electromagnetic-wave shielding device for shielding unnecessary electromagnetic radiation by covering a printed circuit board which generates electromagnetic waves, by a pair of box-like upper and lower shielding cases integrally connected to each other, include an engaged portion provided at a lower shielding case, an engaging portion provided at an upper shielding case of the shielding case pair and engaging with and disengaging from the engaged portion, and pillar-shaped portions being projected from opposing portions of the shielding cases for holding the board between the pillar-shaped portions when the engaged portion of the lower shielding case engages with the engaging portion of the upper shielding case. The printed circuit board held between the pillar-shaped portions is detachably accommodated in the shielding case pair, except for a connect for receiving external signals.

Abstract: A temperature compensated detector includes a series circuit formed by successively connecting a first resistor, a first diode, a second diode having a characteristic substantially equal to that of the first diode, and a second resistor, a third resistor, and a fourth resistor. A terminal supplied with a predetermined bias voltage is grounded through the series circuit. A high-frequency signal to be detected is supplied to a junction point between the first resistor and the first diode or a junction point between the second diode and the second resistor. A detected signal is derived from a junction point between the third resistor and the fourth resistor which are respectively connected to both ends of the second diode or the first diode to divide a voltage.

Abstract: An apparatus for controlling the output power of a transmitter installed in a vehicle or used in a mobile radio communication equipment and more particularly to apparatus and method for accurately measuring and controlling over a wide range the output power of a radio frequency to be transmitted.

Abstract: A circulator section in a transceiver receives a transmit signal and an antenna signal and provides them respectively to an antenna and to an electronic switch. The electronic switch operates synchronously with the duplex mode of the transceiver to connect the antenna to a receiver when the transceiver is in receive mode, and to a matched load when it is in transmit mode. Since the signal path of any portion of the transmit signal reflected by a mismatched antenna is terminated by the load, power which otherwise might be reflected back to the transmitter and thereby damage it is instead absorbed by the matching load.

Abstract: A radiation shield for a hand-held cellular telephone is made up of a metal strip placed between the antenna rod of the telephone and the speaker. The strip has a flat body portion and an upper portion that is curved away from the rod. Overall length of the strip is slightly longer than the antenna rod, and its width is 1 to 1 1/2 inches. Radiation fields reaching the head of a user whose ear is placed near the speaker are substantially reduced by the shield.

Abstract: A device for ameliorating RF radiation received from cellular telephones and the like is disclosed. The device includes at least one spacing member attachable to the cellular telephone so as to maintain the telephone a minimum desired distance from the user while the telephone is in use. The spacer will generally be made of an elastomeric and/or energy absorbing material, so as to be comfortable and minimize the specific energy absorption rate of RF radiation by the user.

Abstract: An optical transceiver unit capable of preventing any crosstalk from an optical transmitter to an optical receiver to thereby avert reduction of the reception sensitivity. The optical transceiver unit comprises a multilayer printed circuit board, a lower case for housing the multilayer printed circuit board therein, and an upper case so disposed as to cover the lower case for enclosing the multilayer printed circuit board in an assembly of the two cases. A light emitting element module and a light receiving element module are attached to one side wall of the lower case. The printed circuit board has a first region where a transmitting circuit is formed, and a second region where a receiving circuit is formed. The first and second regions are completely isolated electromagnetically from each other by a first shield plate fixed to the lower case and a second shield plate fixed to the upper case.

Abstract: An accessory for cellular telephones or marine band telephones that will afford some protection to cellular telephone and marine band telephone users from the alleged brain, head and body damage caused by electro-magnetic radiation and microwave radiation of cellular telephone use or marine band use and to also provide a comfortable handle when using and carrying the cellular telephone or marine band telephone.

Abstract: An abnormal transmission stopping circuit for use in a transmitter including a base band signal processing circuit, an amplitude modulator which modulates the amplitude of a carrier signal in accordance with a base band signal, and a transmission amplifier which amplifies a signal modulated by the amplitude modulator. The stopping circuit includes an electric current detecting circuit which detects a power supply current to the transmission amplifier, and a comparator which generates and supplies a transmitting function stopping signal to the base band signal processing circuit when the detected power supply current exceeds a threshold value.

Abstract: A radio transmitter output power controller which automatically restricts the maximum transmitting time during an averaging time so that the average power remains below an acceptable level. Additionally or alternatively, the maximum transmitter output power may be automatically reduced to a lower level if and when a predetermined average power level is approached. A warning signal may be generated to inform a user that the maximum permitted power output is being approached.

Abstract: A communication device (200) supporting transmissions provides transmission related device temperature control. The communication device (200) has a particular portion (244) subject to an increase in temperature resulting from the transmissions. A message is provided for transmission by the communication device (200) which has a data communication protocol (224) governing message transmission. Temperature control is effected by determining temperature information for the particular portion (244) of the communication device (200) and by modifying operation of the data communication protocol (224) based in part on the temperature information.

Abstract: In portable terminal units each of which has a rechargeable battery and a data processing section, one terminal is used as both a terminal for charging the rechargeable battery and a terminal for connecting a data processing unit to an external data processing unit. First protective circuitry protects the data processing unit from a battery charging current and second protective circuitry eliminates loading of the rechargeable battery due to a data voltage and protects the external data processing unit from charging current for the chargeable battery.

Abstract: A device for shielding a user from electromagnetic waves emitted by a cellular telephone. The device includes a shielding member extending between the antenna of the telephone and a user and configured to encompass the antenna on three sides.

Abstract: A transmitter that includes an amplifying element, an antenna, a gain stage, and a closed loop feedback may compensate for varying antenna loads without an isolator. This may be accomplished by determining the effects of the varying loading on overall loop gain. Knowing the effects, the transmitter adjusts the gain of the gain stage to maintain a constant overall loop gain, thus eliminating the need for an isolator.

Abstract: An RF transmitter protection circuit for providing protection to a power amplifier includes circuitry for sensing the presence of an input excitation signal applied to the input of the power amplifier. Circuitry is provided for monitoring an output signal generated by the power amplifier at the output of the power amplifier and for generating a signal proportional to the output signal. Circuitry is further provided for applying the signal generated by the monitoring circuit to the input of the power amplifier in response to a loss of input signal detected by the sensor.

Abstract: A shielding device used on hand-held cellular phones comprises a substantially rectangular shield which extends adjacent to the antenna. A downwardly extending slide arm portion of the shield terminates in a substantially pointed end surface formed by the outer edge of the shield sloping inwardly to engage the inner edge of the slide arm, said outer edge having a notch on the exterior surface thereof. The device also includes a paddle arm portion extending perpendicular to the shield area and then downwardly to terminate in an enlarged paddle engaging the rear of the phone. The shield is mounted to a hand-held cellular phone with the shield area extending vertically upward adjacent to the antenna and the paddle arm extending over the top of the phone and terminating in the rear paddle and the paddle arm extending over the top of the phone. The shield is held in place by an O-ring which surrounds the phone and fits in the notch in the slide arm.

Abstract: A power control circuit for use in radio transmitters such as portable telephone sets includes a power amplifier for amplifying the power of a transmission signal to obtain an output signal; control circuits for controlling the amplitude of the signal output by the power amplifier; a limiter for partially limiting the amplitude of the signal from the power amplifier in order to obtain a limited signal; a multiplication circuit for multiplying the limited signal from the limiter and part of the signal from the power amplifier in order to acquire a multiplied signal; a low-pass filter for extracting a DC component of the multiplied signal from the multiplication circuit; and a comparison circuit for comparing the DC component from the low-pass filter with a reference voltage in order to obtain a comparison output.

Abstract: A radiation shielding apparatus for a radio transmitting device, such as a cellular phone. A radiation shield is disposed between a radiation component and a user to prevent unwanted exposure of the user to emanating radiation from the radiation emanating component. The cellular telephone radio transmitting device may be a hand-held cellular telephone, and the radiation emanating component may be an internal or external antenna or any other electromagnetic radiation source, such as a transmitter. The radiation shield can be retrofitted to an existing cellular telephone, or may be designed specific for different models of cellular phones. The radiation shield can absorb, block and/or reflect electromagnetic wave radiation to shield the user of such cellular telephones from unwanted and possibly harmful exposure to electromagnetic wave radiation.

Abstract: A cordless telephone handset includes a burst mode transmitter/receiver unit comprising a radio (10) and a current sink (20) shunted across the radio. A controller (18) controls the current sink (20) in a feedback manner such that the sum of the currents drawn by the radio and the current sink is substantially constant, in order to compensate for fluctuations in the current drawn by the radio alone, so as to avoid interference at the burst rate when the handset is used in conjunction with a hearing aid.

Abstract: An amplifier protector and method for preventing power overload of a power amplifier and destruction of transmission circuitry and printed wiring board. The protector continually monitors the peak forward and reflected voltages of the transmitter output which are proportional to the forward and reflected power. An associated processor determines whether the forward voltage is below a threshold voltage which indicates a circuit malfunction. If the circuit malfunction is detected, the processor via an automatic level control circuit turns off the power amplifier in a timely fashion to prevent damage to the transmission circuitry.

Abstract: A personal security system includes at least one movable transmitter adapted to produce an emergency signal transmission when activated and a plurality of transceivers adapted to receive emergency signal transmissions from the movable transmitter. False alarms are avoided by inhibiting multiple transmissions by a movable transmitter within a predetermined time period.

Abstract: An RF power amplifier having amplifier protection is presented wherein an RF source supplies an RF input signal to an actuatable RF power amplifier having an on condition and an off condition for, when on, normally receiving and amplifying the input RF signal to provide an amplified output RF signal. RF current and RF voltage in the output circuit are detected. A first signal is provided from the RF current and exhibits a fixed amplitude but a frequency and phase corresponding with that of the RF current. A second signal is provided of the fixed amplitude and which corresponds in frequency and phase with the RF voltage. The first and second signals are compared so as to provide a phase signal having a magnitude dependent upon the phase difference between the first and second signals. This phase signal is then compared with a reference to provide a turn-off signal in dependence upon the comparison for purposes of actuating an RF power amplifier to its off condition.

Abstract: A transmitter, with an inphase input for receiving an inphase baseband input signal, and a quadrature input for receiving a quadrature baseband input signal, comprises a modulator, coupled to the inphase and quadrature inputs, for modulating the inphase and quadrature baseband signals to provide a modulated radio-frequency signal and a linear amplifier, coupled to the modulator, for amplifying the modulated radio-frequency signal to produce an output signal. Oscillation detector means are coupled to receive the output signal, for detecting oscillation, and for producing an error signal as a result of the oscillation. The transmitter also comprises means for reducing the open loop gain of the feedback loop, disposed between the inphase and quadrature inputs and the modulator. The means for reducing the open loop gain reduces the open loop gain of the transmitter to less than one, in response to the error signal.