Abstract:
PROBLEM TO BE SOLVED: To improve both transmission capacity and communication reliability by selecting an optimal communication method and transmission mode. SOLUTION: There are provided a plurality of systems of reconfigurable radio processing unit 102 whose function and performance can be modified. A control unit 104 collects quality information on the communication link in communication methods received at respective radio processing systems 102a, 102b. According to this, the control unit 104 selects an optimal communication method and transmission mode from a plurality of communication methods and transmission modes (for example, diversity transmission between a plurality of systems, diversity transmission by a single communication method, and MIMO channel multiplex transmission). By modifying configurations of the reconfigurable radio processing unit 102 according to the selected communication method and transmission mode, it is possible to communicate at a desired transmission mode. Thus, it is possible to perform an optimal transmission to the communication link according to the quality condition. COPYRIGHT: (C)2009,JPO&INPIT
Abstract:
PROBLEM TO BE SOLVED: To prevent the generation of grating lobes in an array antenna apparatus. SOLUTION: In the array antenna apparatus provided with antenna elements 21A, 21B and a feeder line 10 which are patterned on an upper substrate 1 and a lower substrate 2, a no-power-supply element 32 is formed so as to be disposed on a position of less than 1/2 wavelength from respective antenna elements 21A, 21B. COPYRIGHT: (C)2009,JPO&INPIT
Abstract:
PROBLEM TO BE SOLVED: To provide an amplifier circuit providing an improved gain.SOLUTION: The amplifier circuit having plural amplifier elements which are cascade-connected to each other includes: a distribution control section that distributes an input signal, outputs a first distribution signal from a first output terminal, and outputs a second distribution signal of an amplitude different from the amplitude of the first distribution signal from a second output terminal; a first amplifier element with a second terminal grounded, which inputs the first distribution signal to a first terminal, and outputs a first amplified signal which is the amplified first distribution signal from a third terminal; and a second amplifier element that inputs the second distribution signal to a first terminal as a bias input, inputs the first amplified signal to a second terminal, and outputs a second amplified signal of the amplified first amplified signal from a third terminal. The phase of the first distribution signal has the same phase as the phase of the second distribution signal.
Abstract:
PROBLEM TO BE SOLVED: To provide a phased-array transmitter in which phase amplitude and amplitude error among a plurality of transmission systems can be detected and corrected by a simple configuration of low power consumption.SOLUTION: The phased-array transmitter includes branch detection units 121, 122 which extract the transmission outputs of a plurality of transmission branches 101, 102 by means of couplers 161, 162, and detect the signal level of each transmission branch thus extracted, and a composition detection unit 130 which detects the output from a signal composition unit 110 compounding the outputs from two transmission branches thus extracted. Output levels of the branch detection units 121, 122 are compared and the amplitude error is detected and corrected, and then the phase error is detected and corrected by the output level of the composition detection unit 130.
Abstract:
PROBLEM TO BE SOLVED: To provide a signal modulation circuit which can control a transmission power even when performing a level adjustment of continuous signals from an oscillation circuit. SOLUTION: A pulse generation circuit as an example of the signal modulation circuit includes: an oscillation circuit; a control signal generation circuit; a multiplication circuit; a filter; and a control unit. The oscillation circuit and the multiplication circuit are active circuits formed by active elements. The oscillation circuit outputs continuous signals, which are input to the multiplication circuit. The multiplication circuit is intermittently operated by the control signal output from the control signal generation circuit, thereby generating a pulse signal. The power level is easily adjusted by the signal from the control unit. COPYRIGHT: (C)2009,JPO&INPIT
Abstract:
PROBLEM TO BE SOLVED: To provide a frequency conversion circuit capable of changing a conversion gain of the frequency conversion circuit. SOLUTION: The frequency conversion circuit 1 comprises an amplifying portion 3 having an amplifier transistor 6 for amplifying an input signal, a switching portion 4 having a pair of differential transistors 7 each mixing the amplified input signal with a local oscillation signal, and a gain switching circuit 5 connected to an interstage D between the amplifying portion 3 and the switching portion 4. The gain switching circuit 5 comprises a capacitor 9 connected to the interstage D and a switch 11 arranged between the capacitor 9 and the earth. If the switch 11 is turned on, a conversion gain of the frequency conversion circuit 1 falls. If the switch 11 is turned off, the conversion gain of the frequency conversion circuit 1 is recovered. The conversion gain of the frequency conversion circuit 1 can be changed by carrying out the on/off control of the switch 11. COPYRIGHT: (C)2009,JPO&INPIT