摘要:
A radio transmitter including a combiner which combines input I/Q signals with feedback I/Q signals, a power amplifier which amplifies the quadrature modulated signal, a detector which detects amplitude and phase differences between the input and feedback I/Q signals, a switch to turn on and off the feedback I/Q signals, a generator to generate control signals which minimizes the amplitude difference and the phase difference, in a state where a transmission power is set, during for a period during which the switch is turned off, an amplitude adjuster which adjusts an amplitude of the feedback RF signal, during a period during which the switch is turned on, and a phase adjuster which adjusts a phase of the local signal, during the period during which the switch is turned on.
摘要:
A MOS resistance controlling device includes: a plurality of MOS transistors having a first MOS transistor to N-th (the integer N is larger than 1) MOS transistor being serially connected, the source of the first MOS transistor being set to a first reference potential, the drain the N-th MOS transistor being set to a second reference potential, and the drain of an I-th MOS transistor being connected to the source of an I+1-th MOS transistor, where I is an integer from 1 to N−1; a current source which is electrically disposed at connection node between the drain of the N-th MOS transistors and the second reference potential; and an operational amplifier having a first input terminal being supplied with a third reference potential, a second input terminal connected with the connection node and an output terminal being connected with gates of the MOS transistors.
摘要:
A MOS resistance controlling device includes: a plurality of MOS transistors having a first MOS transistor to N-th (the integer N is larger than 1) MOS transistor being serially connected, the source of the first MOS transistor being set to a first reference potential, the drain the N-th MOS transistor being set to a second reference potential, and the drain of an I-th MOS transistor being connected to the source of an I+1-th MOS transistor, where I is an integer from 1 to N−1; a current source which is electrically disposed at connection node between the drain of the N-th MOS transistors and the second reference potential; and an operational amplifier having a first input terminal being supplied with a third reference potential, a second input terminal connected with the connection node and an output terminal being connected with gates of the MOS transistors.
摘要:
A radio transmitter including a combiner which combines input I/Q signals with feedback I/Q signals, a power amplifier which amplifies the quadrature modulated signal, a detector which detects amplitude and phase differences between the input and feedback I/Q signals, a switch to turn on and off the feedback I/Q signals, a generator to generate control signals which minimizes the amplitude difference and the phase difference, in a state where a transmission power is set, during for a period during which the switch is turned off, an amplitude adjuster which adjusts an amplitude of the feedback RF signal, during a period during which the switch is turned on, and a phase adjuster which adjusts a phase of the local signal, during the period during which the switch is turned on.
摘要:
A MOS resistance controlling device includes: a plurality of MOS transistors having a first MOS transistor to N-th (the integer N is larger than 1) MOS transistor being serially connected, the source of the first MOS transistor being set to a first reference potential, the drain the N-th MOS transistor being set to a second reference potential, and the drain of an I-th MOS transistor being connected to the source of an I+1-th MOS transistor, where I is an integer from 1 to N−1; a current source which is electrically disposed at connection node between the drain of the N-th MOS transistors and the second reference potential; and an operational amplifier having a first input terminal being supplied with a third reference potential, a second input terminal connected with the connection node and an output terminal being connected with gates of the MOS transistors.
摘要:
An amplifier circuit according to the present invention comprises: a first differential amplifier circuit including a first transistor having a gate terminal forming a first input node, a second transistor having a gate terminal forming a second input node and having a dimensional ratio with respect to the first transistor of K:M (where K>M), and a first current source that supplies a first current to a source terminal of the first transistor and a source terminal of the second transistor; a second differential amplifier circuit including a third transistor having a gate terminal forming a third input node, a fourth transistor having a gate terminal forming a fourth input node and having a dimensional ratio with respect to the third transistor of M:K, and a second current source that supplies a second current to a source terminal of the third transistor and a source terminal of the fourth transistor, the second differential amplifier circuit having a same gain as the first differential amplifier circuit; and a third differential amplifier circuit including a fifth transistor having a gate terminal forming a fifth input node, a sixth transistor having a gate terminal forming a sixth input node and having a dimensional ratio with respect to the fifth transistor of 1:1, and a variable current source that supplies a third current to a source terminal of the fifth transistor and a source terminal of the sixth transistor, wherein the third differential amplifier circuit combines the third current and the fifth transistor so that a gain of the third differential amplifier circuit is greater than a gain of the first differential amplifier circuit when the third current is a first magnitude, and the gain of the third differential amplifier circuit is lower than the gain of the first differential amplifier circuit when the third current is a second magnitude that differs from the first magnitude.
摘要:
An amplifier circuit according to the present invention comprises: a first differential amplifier circuit including a first transistor having a gate terminal forming a first input node, a second transistor having a gate terminal forming a second input node and having a dimensional ratio with respect to the first transistor of K:M (where K>M), and a first current source that supplies a first current to a source terminal of the first transistor and a source terminal of the second transistor; a second differential amplifier circuit including a third transistor having a gate terminal forming a third input node, a fourth transistor having a gate terminal forming a fourth input node and having a dimensional ratio with respect to the third transistor of M:K, and a second current source that supplies a second current to a source terminal of the third transistor and a source terminal of the fourth transistor, the second differential amplifier circuit having a same gain as the first differential amplifier circuit; and a third differential amplifier circuit including a fifth transistor having a gate terminal forming a fifth input node, a sixth transistor having a gate terminal forming a sixth input node and having a dimensional ratio with respect to the fifth transistor of 1:1, and a variable current source that supplies a third current to a source terminal of the fifth transistor and a source terminal of the sixth transistor, wherein the third differential amplifier circuit combines the third current and the fifth transistor so that a gain of the third differential amplifier circuit is greater than a gain of the first differential amplifier circuit when the third current is a first magnitude, and the gain of the third differential amplifier circuit is lower than the gain of the first differential amplifier circuit when the third current is a second magnitude that differs from the first magnitude.
摘要:
A power-saving control apparatus includes a memory storing first to Nth different authentication codes, determines, every time a signal including an authentication code is received, whether the authentication code in the received signal is a valid code which matches one of the authentication codes in the memory, outputs an operation signal to a main apparatus when the authentication code in the received signal is determined to be the valid code, and generates a new authentication code, when (a) the number of times the authentication code in each received signal matches a first authentication code of the authentication codes in the memory is equal to a predetermined value or (b) the authentication code in the received signal matches a second or subsequent authentication code of the authentication codes in the memory, to delete one of the authentication codes in the memory, and to store the new authentication code in the memory.
摘要:
A receiving device includes a rectifier configured to rectify a received signal and a bias supply unit configured to intermittently supply the rectifier with a bias voltage corresponding to a threshold voltage of the rectifier. The receiving device further includes a detector configured to detect the received signal based on an output of the rectifier and a controller configured to control the bias supply unit to stop supplying the bias voltage upon detection of the received signal by the detector.
摘要:
According to one embodiment, a receiving apparatus includes a variable gain amplifier, comparator, and signal processor. The comparator compares a signal level of the second signal with a first threshold to generate a third signal, a signal level of the third signal being set to a high signal if the signal level of the second signal is greater than the first threshold. The signal processor determines presence of a signal if a rate of high signals in third signals for a period is greater than a second threshold. The second threshold is set to a first value when the control of the gain is performed and set to a second value when the demodulation processing is performed. The first value is greater than the second value.