摘要:
A distortion compensating device provided in a receiver for compensating distortion which is added to a signal in a transmission path. The signal is generated in a multi-level modulator of a transmitter in which a digital signal is mapped to one of a plurality of specified signal points in a signal space diagram. The device includes a signal-point-position averaging circuit for producing an average signal point for each of a plurality of distributions of received signal points in the signal space diagram. A discrimination circuit in the device discriminates the average signal point closest to a received signal point from other average signal points in the signal space diagram.
摘要:
A distortion compensating device provided in a receiver for compensating distortion which is added to a signal in a transmission path. The signal is generated in a multi-level modulator of a transmitter of which a digital signal is mapped to one of a plurality of specified signal points in a signal space diagram. The device includes discrimination circuits for discriminating a received signal according to threshold lines partitioning the signal space diagram into discrimination areas, the threshold lines being defined so that the discrimination areas on an outer side of the signal space diagram having each an area greater than an area of each of the discrimination areas on an inner side of the signal space diagram and a selection circuit for selecting one of a plurality of threshold line patterns based on a level of the received signal which is discriminated according to a selected threshold line pattern.
摘要:
A distortion compensating device provided in a receiver for compensating distortion which is added to a signal in a transmission path. The signal is generated in a multi-level modulator of a transmitter in which a digital signal is mapped to one of a plurality of specified signal points in a signal space diagram. The device includes a signal-point-position averaging circuit for producing an average signal point for each of a plurality of distributions of received signal points in the signal space diagram. A discrimination circuit in the device discriminates the average signal point closest to a received signal point from other average signal points in the signal space diagram.
摘要:
The invention provides an automatic amplitude equalizer for compensating an amplitude characteristic of an input signal, wherein a control signal for equalizing an inclination amplitude distortion of an input signal is detected making use of a pair of digital demodulated signals to compensate for the amplitude characteristic of the input signal with a high degree of accuracy and which can be constructed with a reduced circuit scale and at a reduce cost. The automatic amplitude equalizer includes a first-order inclination amplitude equalization section for compensating for an amplitude characteristic of an input signal in accordance with a first-order inclination amplitude characteristic, and a control section for discriminating a direction of variation of a value of a first one of a pair of digital demodulated signals originating from the input signal, detecting error information from the other, second one of the digital demodulated signals which is orthogonal to the first signal, and outputting a control signal for the first-order inclination amplitude equalization section based on a correlation between the error information and the direction of variation of the value of the first signal.
摘要:
A fractionally spaced cross-polarization interference canceller, wherein a compensation signal is generated through an adaptive filter operating in a frequency that is an integer multiple of a transmission data frequency. The cross-polarization interference canceller includes a mechanism for generating an error signal used to control coefficients of the adaptive filter in the integer multiple frequency. The mechanism is realized, for example, by using a waveform generator generating an estimate of a baseband signal in the integer multiple frequency using a plurality of estimates of transmission data and coefficients determined by an impulse response of a transmission path.
摘要:
A cross polarization interference canceler includes a digital conversion unit for subjecting a demodulated signal of one channel to an analog-to-digital conversion out of two channels which are independently formed, using carriers having the same frequency but having planes of polarization which are mutually orthogonal. An interference canceling unit is provided for canceling interference caused by the other channel of the two channels, with respect to the demodulated signal which is digitally converted by the digital conversion unit. The canceler further includes an integrator for carrying out an integration process with respect to the demodulated signal which is digitally converted by the digital conversion unit so as to provide a negative feedback to the digital conversion unit.
摘要:
An optical sensor has an optical block including a substrate, a light-emitting element formed on the substrate, and a light-receiving element formed on the substrate by using an adjusting member for arranging side-by-side with the light-emitting element, a light-transmitting member located between the optical block and an object, and connecting terminal optically connected to the light-emitting element and the light-receiving element. It is preferable that the light-transmitting member is separated into a plurality of light transmitting members in correspondence with areas separated on the object. There is also provided an optical sensor having a light-transmitting member, a plurality of incident optical fibers, optically coupled with the light-transmitting member, for transmitting light emitted from a light-emitting element to the light-transmitting member, a plurality of outgoing optical fibers, optically coupled with the light-transmitting member, for transmitting light passed through the light-transmitting member after being reflected on an object to the light-receiving element, and a housing for integrally housing the light-transmitting member, the incident optical fiber, and the outgoing optical fibers.
摘要:
A molded circuit board is constructed by forming a plurality of resin moldings integrally with a circuit film including an insulating film and circuit pattern on the insulating film, spaced specified distances therebetween, on one side of the circuit film. The plurality of moldings can be assembled into an electronic device box by bending the intermediate portion, between the moldings, of the circuit film.
摘要:
An insulating sheet having through holes formed therein at positions where circuit patterns formed on its both surfaces are electrically connected is prepared. A sheet for forming a hole bottom is attached to one surface of the insulating sheet. Subsequently, a first-layer circuit pattern is printed on the other surface of the insulating sheet to which the hole-bottom sheet is not attached, and a conductive paste is filled into the holes. Thereafter, the hole-bottom sheet is removed. Then, a second-layer circuit pattern is printed on the surface of the insulating sheet, from which the hole-bottom sheet is removed. With this process, a two-layer printed circuit sheet is manufactured.
摘要:
A reinforcing fastener for fastening a chemical connector and an electronic circuit includes a substantially cylindrical section shaped element having edges defining an axial slit, wherein the element is formed of an alloy having both superelastic and shape memory properties. The slit is of such a size at a temperature below the Martensite transformation temperature of the alloy that the alloy is superelastically deformed when the slit is maintained at the same size while the alloy is above the Martensite transformation temperature. This results in the chemical connector being fastened to the electronic circuit with a substantially constant force over time.