Abstract:
PROBLEM TO BE SOLVED: To reduce power consumption, and also to reduce a circuit scale, in a receiver in a super-heterodyne system achieved by using a DSP. SOLUTION: A high frequency analog signal received through an antenna 1 is temporarily converted into a low frequency analog signal by a first frequency conversion circuit 4, and A/D converted, and the generated digital signal is subject to digital signal processing by a DSP 9, and returned to an analog signal, and frequency-converted into a signal of a target intermediate frequency by a second frequency conversion circuit 12. Thus, it is necessary only to A/D convert the analog signal whose frequency is lower than the intermediate frequency by an A/D converter 8. Also, it is unnecessary not only to carry out high speed sampling, based on a Nyquist theorem, but also to operate even the DSP 9 with high sampling frequency. COPYRIGHT: (C)2008,JPO&INPIT
Abstract:
PROBLEM TO BE SOLVED: To facilitate forming an IC in a loop antenna input circuit for an AM radio receiver by eliminating the necessity of an impedance conversion circuit using a transformer without causing an increase in a current noise. SOLUTION: A pair of p-MOSFETs 21, 22 used as amplifier elements for amplifying an input signal from a loop antenna 1 are directly connected to the loop antenna 1. With this configuration, the input signal from the loop antenna 1 can be received by the p-MOSFETs 21, 22 at a high impedance. Thus, a transformer for transforming the signal into high impedance is not required, and the impedance of the loop antenna 1 itself is not required to increase, thereby suppressing a current noise. COPYRIGHT: (C)2008,JPO&INPIT
Abstract:
PROBLEM TO BE SOLVED: To improve quality of an image to which an image effect is given by pixel value conversion processing using a correction factor. SOLUTION: Using correction value tables 2 -1 -2 -k having patterns varied according to the positional relationship of two pixels from which a difference value is calculated, a correction value is not decided simply according to the difference value but decided in compliance with both of the positional relationship between the pixels and the difference value between them, so that a proper correction value can be decided while selecting the positions of the pixels. In comparison with a conventional technology by which the correction value is simply changed for changing an emphasis degree, for example, quality of the image acquired by a pixel value conversion processing can be improved. COPYRIGHT: (C)2008,JPO&INPIT