摘要:
When the radio circuit apparatus is transmitting, the output signal of the first local oscillator 102 is inputted to the transmitted frequency converter 112 as well as to the frequency divider 104, and then the output signal of the frequency divider 104 is inputted to the modulator 111. The modulator 111 modulates the output signal of the frequency divider 104 with a base band signal. The output signal of the modulator 111 is inputted to the transmitted frequency converter 112, to be converted to the frequency of a transmitted signal by the output signal of the first local oscillator 102. When the radio circuit apparatus is receiving, the output signal of the low noise amplifier 121 is inputted to the first frequency converter 122 to be converted to the first intermediate frequency by the output signal of the first local oscillator 102. The output signal of the filter 123 is inputted to the second frequency converter circuit 124 to be converted to the second intermediate frequency by the output signal of the second local oscillator 103. Thereby, unnecessary components for transmission can be easily lowered to make it possible to miniaturize the radio circuit apparatus.
摘要:
The transmission apparatus according to the present invention can reduce transmission output noise leaking into the receiving apparatus even when the transmission apparatus is applied to wireless equipment using the W-CDMA scheme. Transmission apparatus (100) has bypass circuit (101) and bypass control circuit (103) that inputs an RF phase signal to power amplifier (14) via amplitude adjustment circuit (16) when bypass circuit (101) and power amplifier (14) are operated in non-saturation mode, and that inputs the RF phase signal to power amplifier (14) via bypass circuit (101) when power amplifier (14) is operated in saturation mode.
摘要:
There provides a two-point modulation phase modulation apparatus capable of obtaining an RF phase modulation signal of superior modulation precision with low power consumption and a simple configuration even in the event of inputting a wide band baseband modulation signal. A differentiator (21) of the opposite characteristics to the attenuation characteristics of anti-alias filter (22) is provided at the front stage of a D/A converter (6). As a result, it is possible to sufficiently suppress an alias signal without raising the sampling frequency of the D/A converter (6) (i.e. low power consumption) using an anti-alias filter (22) of a simple configuration (i.e. low cost) with a low order for a narrower bandwidth than a PLL modulation frequency bandwidth, and it is possible to obtain an RF phase modulation signal where the entire frequency band of input digital baseband modulation signal (S1) is reflected in a superior manner.
摘要:
Provided is a transmission modulation apparatus, using polar modulation of two-point modulation scheme, capable of completing a timing adjustment of a BB phase modulation signal and BB amplitude modulation signal in a short time. A phase modulation section (10) that performs two-point modulation with a PLL circuit is provided with a switch (17) to make the PLL circuit open loop, and when a first delay section (5) corrects the deviation in synchronization between the BB phase modulation signal and BB amplitude modulation signal, the switch (17) is turned off to make the PLL circuit open loop.
摘要:
A problem of the present invention is to provide a wide band modulation PLL having good modulation accuracy at low cost. With respect to a PLL having a VCO (21), a frequency divider (22), a phase comparator (23), a charge pump (24) and a loop filter (25), the VCO (21) and a frequency dividing ratio of the frequency divider (22) are controlled to perform modulation. The VCO (21) has two control terminals for PLL and modulation, and a control signal generation part (28) generates a control voltage Vtm of the VCO (21) based on phase modulation data and an input voltage Vtl to the control terminal for PLL. At the time of adjusting a modulation factor, the control voltage Vtm to the control terminal for modulation of the VCO (21) is controlled and also the input voltage Vtl is measured and a modulation sensitivity of a frequency of the VCO (21) to Vtm is calculated and a modulation factor of the phase modulation data is adjusted based on the modulation sensitivity obtained.
摘要:
An object of the invention is to provide wideband modulator using a PLL synthesizer which can match the frequency characteristic and prevent degradation in modulation accuracy even in the presence of a variation in the manufacture of circuit components. In a wideband modulator which modulates the division ratio of a frequency divider by using a modulating signal generated by a modulating signal generator and outputs a modulated carrier signal from a VCO, first and second calibration data from a calibration data generator are input via a selector. The amplitude value of an ac component of each modulating signal appearing on the output of a loop filter or the amplitude value of an ac component of each modulating signal demodulated by a demodulator is converted to a digital value by way of an AID converter. The difference between the two is detected by error detection means and a control signal FCR to eliminate the difference is generated by frequency characteristic correction means in order to correct the frequency characteristic of a PLL or a pre-distortion filter.
摘要:
A two-point frequency modulation apparatus is proposed whereby the spectrum of transmission waves is kept within the spectrum mask. Voltage is supplied to the control voltage terminal of VCO 1 in accordance with modulation data via noise shaper 101 that has operating characteristics of attenuating more noise at higher frequencies. As a result, by virtue of the working of noise shaper 101, the signal level outputted from the PLL circuit combining the modulation signal and the quantization noise decreases in proportion to the distance form the central frequency, so that two-point frequency modulation apparatus 100 is made possible whereby the spectrum of an RF modulation signal is kept within the spectrum mask.
摘要:
A touch panel is constructed of a top sheet member having a resistive membrane on its inner surface and a base sheet member having a resistive membrane on its inner surface, the top and base sheet members facing each other with dot spacers being located in between. The top sheet member is formed by laminating a bulge-resistant film, a polarizing plate, a quarter wavelength plate, and a light isotropic film in this order from above. The base sheet member is constructed of a glass sheet and a reinforcement film whose thermal linear expansion coefficient is almost the same as the thermal linear expansion coefficient of the polarizing plate or the quarter wavelength plate included in the top sheet member, the reinforcement film being adhered to the lower surface of the glass sheet.
摘要:
A touch panel is constructed of a top sheet member having a resistive membrane on its inner surface and a base sheet member having a resistive membrane on its inner surface, the top and base sheet members facing each other with dot spacers being located in between. The top sheet member is formed by laminating a bulge-resistant film, a polarizing plate, a quarter wavelength plate, and a light isotropic film in this order from above. A PET film which is not heat-treated so as to have a higher thermal contraction rate than the other members of the top sheet member underneath such as the polarizing plate, is used as the bulge-resistant film. Since the bulge-resistant film contracts more than the polarizing plate under a high ambient temperature, after the ambient temperature returns to normal, the bulge-resistant film does not become slack against the polarizing plate. Accordingly, the top sheet member can be kept from bulging outward.