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61. 发明专利

AU2456592A RADIO TELEPHONE APPARATUS 未知
公开(公告)号：AU2456592A
公开(公告)日：1993-03-25
申请号：AU2456592
申请日：1992-09-16
申请人： NEC CORPORATION
发明人： TOSHIHIRO HARA
IPC分类号： H04B7/24 , H04B1/56 , H04B7/26 , H04J3/00 , H04L5/16 , H04M1/725
摘要： A radio telephone apparatus of the TDMA/TDD system includes a frequency division orthogonal modulator (111) including a frequency divider (210) for dividing by four a local signal having a frequency which is four times that of the intermediate frequency to obtain a carrier having a frequency shifted from that of the local signal by 90 DEG . The signal to be modulated is subjected to an orthogonal modulation in mixers (203A, 203B) according to the carrier wave to produce an intermediate frequency carrier. The operation of the modulator is stopped in a signal reception state by a signal at a power down terminal (209) to prevent the intermediate frequency carrier from being produced. Signal transmission and reception are conducted using carriers having different frequencies. By these measures cochannel interference from the transmitter entering the receiver in the same housing is reduced.

62. 发明专利

AU635096B2 MOBILE RADIO COMMUNICATION APPARATUS 未知
公开(公告)号：AU635096B2
公开(公告)日：1993-03-11
申请号：AU6796790
申请日：1990-12-11
申请人： NEC CORPORATION
发明人： YUKIO YOKOYAMA
IPC分类号： H01Q13/08 , H01Q1/24 , H01Q9/04 , H01Q9/36 , H01Q9/42 , H04B1/38 , H04Q7/32 , H04W88/02
摘要： A mobile radio communication apparatus with an improved antenna for promoting easy manual operations, insuring desirable acoustic characteristics, and preventing the antenna gain from being lowered by user's head or hand during communication. An antenna is mounted on the upper surface of a casing and made up of a rectangular first conductive plate parallel to and spaced apart from the upper surface by a predetermined distance and having a length L1, a rectangular second conductive plate extending perpendicularly from the first conductive plate and having a height H2, and a rectangular third conductive plate extending perpendicularly from the second conductive plate and in parallel to the first conductive plate. A short-circuiting plate extending perpendicularly from one side of the first conductive plate by a height H1 and has a length M as measured in a direction parallel to the length L1. The short-circuiting plate has the end thereof connected and affixed to the upper end of a particular surface of the casing where the earpiece, mouthpiece and operation secton are arranged. The height H1 of the short-circuiting plate is greater than said height H2 of the second conductive plate, while the length M of the short-circuiting plate is equal to or smaller than the length L1 of the first conductive plate.

63. 发明专利

AU2216492A RADIO TRANSCEIVER 未知
公开(公告)号：AU2216492A
公开(公告)日：1993-03-11
申请号：AU2216492
申请日：1992-09-04
申请人： NEC CORPORATION
发明人： YUKIO YOKOYAMA , HIROYUKI IWASAKI
IPC分类号： H01Q1/24 , H04B1/18 , H04B1/40
摘要： A radio transceiver having an improved impedance matching characteristics between a rod-like antenna and transmitting and receiving portions thereof. An impedance matching circuit is provided between the antenna and a duplexer to impedance-match therebetween at a frequency within a desired signal frequency band. A transmitting signal and a receiving signal may have substantially different frequencies in which case the impedance matching circuit operates preferrably at center frequencies of these signals, respectively. The impedance matching circuit includes a first inductor inserted between the antenna and the duplexer, a first capacitor inserted between the antenna and ground potential and a parallel resonance circuit composed of a parallel circuit of a second capacitor and a second inductor inserted between the duplexer and ground potential.

64. 发明专利

AU2105392A DATA DISPLAY RADIO PAGER 未知
公开(公告)号：AU2105392A
公开(公告)日：1993-02-18
申请号：AU2105392
申请日：1992-08-14
申请人： NEC CORPORATION
发明人： TERUYUKI MOTOHASHI , KAZUMORI YAMADA
IPC分类号： H04Q7/14 , G08B5/22
摘要： A data display radio pager for producing, on receiving a signal including a preassigned address number, an alert and displaying a message also included in the signal, on a display. When the radio pager receives a signal including a message with time data, it again alerts the user of the radio pager and displays the message on the display at a particular time based on the time data contained in the message.

65. 发明专利

AU2076892A INTEGRATED-CIRCUIT SAMPLED-AND-HOLD PHASE DETECTOR WITH INTEGRATED-CURRENT SETTING RESISTOR 未知
公开(公告)号：AU2076892A
公开(公告)日：1993-02-04
申请号：AU2076892
申请日：1992-08-03
申请人： NEC CORPORATION
发明人： MASAKI ICHIHARA
IPC分类号： H03L7/091 , H03D13/00
摘要： A sample-and-hold phase detector comprises a first charge/discharge circuit for charging a first storage capacitor with a constant current for a duration corresponding to a phase difference between an input pulse and a reference pulse and discharging it after it is sampled. A first sample-and-hold circuit samples the voltage developed in the first storage capacitor to represent the phase difference between the input pulse and the reference pulse. A second charge/discharge circuit periodically charges a second storage capacitor with a constant current for a fixed time interval and discharging it after it is sampled. A second sample-and-hold circuit samples the voltage developed in the second storage capacitor. A current setting circuit, in which a current setting resistor is provided, is connected to both charge/discharge circuits to determine their constant charging currents. A differential integrator provides differential integration on the voltage from the second sample-and-hold circuit with respect to a reference voltage to control the current setting circuit in a feedback loop.

66. 发明专利

AU2069592A LOCAL OSCILLATING FREQUENCY SYNTHESIZER FOR USE IN A TDMA SYSTEM 未知
公开(公告)号：AU2069592A
公开(公告)日：1993-02-04
申请号：AU2069592
申请日：1992-07-30
申请人： NEC CORPORATION
发明人： JUN JOKURA
IPC分类号： H03L7/18 , H03L7/23 , H04B7/24 , H04J3/00 , H04J3/14 , H04L7/00
摘要： A local oscillating frequency synthesizer for a station of a TDMA system includes a pair of synthesizers (1, 2), one being used for generating synchronizing frequencies for monitoring communication channels comprising transmission and reception slots, and the other for generating synchronizing frequencies for monitoring the electric field level of another station, when information is read out from idle slots rather than the transmission and reception slots. Therefore, without using a high speed frequency switching synthesizer such as a direct digital synthesizer or the like changes in frequency synchronization can be achieved in a short period of time by using a selector means (3) to switch between the frequency synthesizers (1, 2) and a local oscillating portion which is low in power consumption can be obtained.

67. 发明专利

AU633270B2 ARRAY ANTENNA DEVICE HAVING IC UNITS WITH IF CONVERSION CIRCUITS FOR COUPLING ANTENNA ELEMENTS AND SIGNAL COMBINER 未知
公开(公告)号：AU633270B2
公开(公告)日：1993-01-28
申请号：AU4142189
申请日：1989-09-13
申请人： NEC CORPORATION
发明人： TOSHIO IMAI , KAZUHIDE SHIBATA , YUGI HIGUCHI
IPC分类号： H01Q3/36 , H01Q21/00 , H05K1/02 , H05K1/18

68. 发明专利

AU2041592A OUTPUT LEVEL CONTROL CIRCUIT FOR USE IN RF TRANSMITTER 未知
公开(公告)号：AU2041592A
公开(公告)日：1993-01-21
申请号：AU2041592
申请日：1992-07-20
申请人： NEC CORPORATION
发明人： SHINICHI MIYAZAKI
IPC分类号： H03G3/20 , H04B1/04
摘要： An output level control circuit for radio-frequency transmitter which intermittently transmits radio-frequency carrier waves such as seen in the TDMA radio communication system and the digital cellular mobile telephone system. The variable gain amplifier unit of this transmitter amplifies the transmitting signal to a predetermined output power level in response to a control signal, the output power level is detected by a detecting diode which receives the application of a temperature-compensated bias voltage, and the sum of the detected output and the bias voltage becomes the detection output to the control loop. The bias voltage of the detecting diode is stored by bias voltage detection means during the off-period of the transmitting signal, an input reference voltage that is supplied in synchronism with the turning-on of the transmitting signal and the stored bias voltage are added by reference signal addition means, and the added output is served as the reference voltage that corresponds to the predetermined output power level. Power control means generates the control signal in response to the added output and the detection output, and the control signal controls the output power level of the variable gain amplifier unit.

69. 发明专利

AU631337B2 TRANSFORMERLESS POWER MONITOR CIRCUIT HAVING MEANS FOR ELECTRONICALLY LATCHING DC ALARMS 未知
公开(公告)号：AU631337B2
公开(公告)日：1992-11-19
申请号：AU6804790
申请日：1990-12-13
申请人： NEC CORPORATION
发明人： TORU KIDO
IPC分类号： G05F1/10 , G06F1/30 , H02M7/06

70. 发明专利

CA2050430A1 FOLDABLE PORTABLE TELEPHONE 未知
公开(公告)号：CA2050430A1
公开(公告)日：1992-03-01
申请号：CA2050430
申请日：1991-08-30
申请人： NEC CORPORATION
发明人： TAMURA, YOSHIHARU , KOJIMA, TATSURU
IPC分类号： H04M1/02
摘要： A foldable portable telephone which allows the user to operate a power switch thereof and to see the ON/OFF state of the switch as well as a reception state even when put in the user's breast pocket in a folded position. A first and a second casing accomodating a transmitter and a receiver, respectively, are foldably connected together by a hinge mechanism. Indications or indicator indicative of the ON/OFF state of the power switch, an indicator for alerting the user to a call, and an opening for a sounder which produces an alert toner are positioned on or in close proximity to the ends of the casings which are remote from the hinge mechanism.

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