Abstract: A power adjustment method includes: measuring output power that is obtained when input power to be amplified in a linear region is input to a power amplifier configured to amplify input power linearly in the linear region and amplify input power nonlinearly in a nonlinear region; deriving a straight line connecting a measurement point corresponding to the measured output power and a boundary point between the linear region and the nonlinear region in a coordinate plane representing input/output characteristics; acquiring information on an approximate equation that is stored in advance in correspondence with the measured output power, the approximate equation representing a relation between input power and output power in the nonlinear region; and storing information on the derived straight line and the acquired information on the approximate equation in a semiconductor integrated circuit provided at a preceding stage of the power amplifier.

Abstract: A power adjustment method includes: measuring output power that is obtained when input power to be amplified in a linear region is input to a power amplifier configured to amplify input power linearly in the linear region and amplify input power nonlinearly in a nonlinear region; deriving a straight line connecting a measurement point corresponding to the measured output power and a boundary point between the linear region and the nonlinear region in a coordinate plane representing input/output characteristics; acquiring information on an approximate equation that is stored in advance in correspondence with the measured output power, the approximate equation representing a relation between input power and output power in the nonlinear region; and storing information on the derived straight line and the acquired information on the approximate equation in a semiconductor integrated circuit provided at a preceding stage of the power amplifier.

Abstract: A radio communication circuit includes a power amplifier configured to amplify a signal and output the amplified signal, an envelope detector configured to extract an envelope of an input signal inputted to the power amplifier, an offset generator configured to generate an offset value for a power supply voltage to be applied to the power amplifier, based on a distortion amount in an output signal from the power amplifier, and a power supply voltage modulator configured to control the power supply voltage to be applied to the power amplifier based on the envelope extracted and the offset value generated.

Abstract: A radio communication circuit includes a transmitter that includes a modulator modulates a signal with a first modulation scheme and a power amplifier amplifies the signal modulated with the first modulation scheme and output the amplified signal and transmits the amplified signal, a receiver that includes a demodulator demodulates the signal output from the transmitter with a second modulation scheme that is different from the first modulation scheme, a pre-distortion compensator compensates occurred upon the amplification of the signal, of the signal input to the transmitter, based on the demodulated signal and a power controller controls supply of power to the receiver and the pre-distortion compensator and stop the supply of the power based on an average power level of the signal output from the transmitter and a peak-to-average power ratio that is a ratio of an instantaneous peak power level to the average power level.

Abstract: A radio communication circuit includes a transmitter that includes a modulator modulates a signal with a first modulation scheme and a power amplifier amplifies the signal modulated with the first modulation scheme and output the amplified signal and transmits the amplified signal, a receiver that includes a demodulator demodulates the signal output from the transmitter with a second modulation scheme that is different from the first modulation scheme, a pre-distortion compensator compensates occurred upon the amplification of the signal, of the signal input to the transmitter, based on the demodulated signal and a power controller controls supply of power to the receiver and the pre-distortion compensator and stop the supply of the power based on an average power level of the signal output from the transmitter and a peak-to-average power ratio that is a ratio of an instantaneous peak power level to the average power level.

Abstract: A radio communication circuit includes a power amplifier configured to amplify a signal and output the amplified signal, an envelope detector configured to extract an envelope of an input signal inputted to the power amplifier, an offset generator configured to generate an offset value for a power supply voltage to be applied to the power amplifier, based on a distortion amount in an output signal from the power amplifier, and a power supply voltage modulator configured to control the power supply voltage to be applied to the power amplifier based on the envelope extracted and the offset value generated.

Abstract: A gain control circuit has a transmission power amplifier that amplifies a transmission signal to a predetermined level. An adjacent channel leak power ratio monitor finds a ratio of a distortion element corresponding to an adjacent channel leak power to a main element from an output signal supplied from the transmission power amplifier, and outputs the found ratio as an ACPR monitor value. A power supply control section variously controls power supply to the transmission power amplifier with use of the ACPR monitor value supplied from the adjacent channel leak power ratio monitor. A transmission signal level variable section controls a gain of a transmission signal path on the basis of a transmission level monitor value supplied from the adjacent channel leak power ratio monitor, thereby varying a level of the transmission signal.

Abstract: A gain control circuit has a transmission power amplifier that amplifies a transmission signal to a predetermined level. An adjacent channel leak power ratio monitor finds a ratio of a distortion element corresponding to an adjacent channel leak power to a main element from an output signal supplied from the transmission power amplifier, and outputs the found ratio as an ACPR monitor value. A power supply control section variously controls power supply to the transmission power amplifier with use of the ACPR monitor value supplied from the adjacent channel leak power ratio monitor. A transmission signal level variable section controls a gain of a transmission signal path on the basis of a transmission level monitor value supplied from the adjacent channel leak power ratio monitor, thereby varying a level of the transmission signal.

Abstract: A gain control circuit has a transmission power amplifier that amplifies a transmission signal to a predetermined level. An adjacent channel leak power ratio monitor finds a ratio of a distortion element corresponding to an adjacent channel leak power to a main element from an output signal supplied from the transmission power amplifier, and outputs the found ratio as an ACPR monitor value. A power supply control section variously controls power supply to the transmission power amplifier with use of the ACPR monitor value supplied from the adjacent channel leak power ratio monitor. A transmission signal level variable section controls a gain of a transmission signal path on the basis of a transmission level monitor value supplied from the adjacent channel leak power ratio monitor, thereby varying a level of the transmission signal.

Abstract: A squaring circuit squares a radio transmission signal. A band-pass filter extracts a spectrum component corresponding to a desired channel, from that low-frequency component of the output of the squaring circuit, which occurs with a center thereof being present near a DC (Direct Current). A level measuring circuit measures the level of the extracted spectrum component. On the other hand, another band-pass filter extracts, from the output of the squaring circuit, a spectrum component corresponding to spectrum spreading due to a distortion in a transmission circuit. Another level measuring circuit measures the level of this extracted spectrum component. A level radio measuring circuit measures a ratio between the level measured by the level measuring circuit and the level measured by the other level measuring circuit, and produces the measured result as a ratio of a leak power to an adjacent channel.

Abstract: For use in a radiocommunication system using a frequency band close to a frequency band of a different radiocommunication system, a radiocommunication device, or a mobile, is controlled so that a maximum of transmission power is set according to an up-link frequency in use. The closer the up-link frequency in use is to the frequency band of the different radiocommunication system, the lower the maximum of transmission power is set.

Abstract: A low-noise amplifier 500a having low-distortion characteristics (low distortion LNA), a low-noise amplifier 500b of a low current consumption type(low current consumption LNA), and radio-frequency switches 502 and 509 for selectively switching either of them are provided in a receiving radio-frequency unit 103. On the basis of a mode changing control function of a CPU 113, an LNA switch control signal AS is generated so that the low-distortion LNA 500a is selected during a period in which the operation of a radio transmitter-receiver is in a transmitting/receiving state, and that the low current consumption LNA 500b is selected in a period of a standby state, and thus the switching of the radio-frequency switches 502 and 509 of a low-noise amplifier circuit section 501 is controlled.

Abstract: A gain control circuit has a transmission power amplifier that amplifies a transmission signal to a predetermined level. An adjacent channel leak power ratio monitor finds a ratio of a distortion element corresponding to an adjacent channel leak power to a main element from an output signal supplied from the transmission power amplifier, and outputs the found ratio as an ACPR monitor value. A power supply control section variously controls power supply to the transmission power amplifier with use of the ACPR monitor value supplied from the adjacent channel leak power ratio monitor. A transmission signal level variable section controls a gain of a transmission signal path on the basis of a transmission level monitor value supplied from the adjacent channel leak power ratio monitor, thereby varying a level of the transmission signal.

Abstract: A squaring circuit squares a radio transmission signal. A band-pass filter extracts a spectrum component corresponding to a desired channel, from that low-frequency component of the output of the squaring circuit, which occurs with a center thereof being present near a DC (Direct Current). A level measuring circuit measures the level of the extracted spectrum component. On the other hand, another band-pass filter extracts, from the output of the squaring circuit, a spectrum component corresponding to spectrum spreading due to a distortion in a transmission circuit. Another level measuring circuit measures the level of this extracted spectrum component. A level radio measuring circuit measures a ratio between the level measured by the level measuring circuit and the level measured by the other level measuring circuit, and produces the measured result as a ratio of a leak power to an adjacent channel.

Abstract: For use in a radiocommunication system using a frequency band close to a frequency band of a different radiocommunication system, a radiocommunication device, or a mobile, is controlled so that a maximum of transmission power is set according to an up-link frequency in use. The closer the up-link frequency in use is to the frequency band of the different radiocommunication system, the lower the maximum of transmission power is set.

Abstract: In a design of the printed circuit board design device, a signal wire name is affixed to each wiring of a circuit, thereby making it quite easy to go through confirmation works after the design works are thoroughly accomplished. The present invention aims at improving efficiency of works for affixing the signal wire name. For this purpose, the signal wire names are input for each desired area of the circuit. By taking full advantage of overlap of the area concerned, the signal wire names connected in serial form are affixed to one wiring. The candidates of the signal wire names to be affixed are tabulated as a list. After the signal wire names are affixed to each wiring of the circuit, the wiring can be retrieved and shown in visible display. In this case too, the candidates of the signal wire names to be retrieved can be tabulated as a list.

Abstract: A phase detection system in which an original modulation signal is detected from a first complex baseband signal obtained through orthogonal demodulation of an FM signal and output, a second complex baseband signal having cosine and sine components of a phase change .DELTA..phi. of the first complex baseband signal in a predetermined time interval .tau. is rotated until a rotation angle .theta. becomes .DELTA..phi., and rotation angle data indicative of the rotation angle .iota. is detected and output.

Abstract: An FSK signal receiving device is constituted by a first phase shifting circuit for applying a first phase shift to a first reception base band signal of first and second reception base band signals having orthogonal phases to generate a third base band signal, and generating a fourth base band signal having a phase orthogonal to the phase of the third base band signal, a second phase shifting circuit for applying the first phase shift to the second base band signal to generate a fifth reception base band signal, and a logical gate circuit for performing an exclusive OR operation on the third and fourth base band signals to obtain a first output signal, on the third and fifth base signals to obtain a second output signal, and on the first and second output signals to generate a detection signal.