摘要:
The present invention relates to an all n-type transistor current mirror for mirroring an input current to an output current. The current mirror comprises an input n-type transistor (T4, QO, T1) interposed between a positive supply plane (VCC) and an input node (104, 202, 310) with its collector being connected to the positive supply plane (VCC) and its emitter being connected to the input node (104, 202, 310). An output n-type transistor (T3, Q1, T2) is interposed between the positive supply plane (VCC) and an output node (106, 204, 314) with its collector being connected to the positive supply plane (VCC) and its emitter being connected to the output node (106, 204, 314). A feedback circuit equals base-emitter voltages of the input (T4, QO, T1) and the output transistor (T3, Q1, T2) in order to mirror the emitter current of the input transistor (T4, QO, T1) to the emitter current of the output transistor (T3, Q1, T2). The all n-type transistor current mirror is highly advantageous by overcoming the shortcomings of technologies such as MOBI3, GaAs, and InP of being unable to provide p-type transistors.
摘要:
An electronic device comprising a passive harmonic-rejection mixer (400) and a calibration circuitry (425). The passive harmonic rejection mixer has an input (102) connected to several sub-mixer stages (402), and the sub-mixer stages are connected to a summing module (406, 408) for generating the output (104). Each sub-mixing stage comprises a gating module (414), an amplifier (416), and a weighting module (418), the gating module selectively passing the input signal or the input signal with inverted polarity under the control of control signals. The calibration circuitry (425) is adapted to input a reference signal (430) to the input of the mixer, receive an output signal (104) from the output of the mixer, and set the weights (K1, K2, K3, K4) of the weighting modules to make the output signal match an expected output signal.
摘要:
The invention relates to frequency conversion systems, in particular for use as up-converters or down-converters in radiofrequency (RF) receivers or transmitters, exemplary embodiments including a radiofrequency receiver including an RF signal input; a mixing module including a first plurality of IF amplifiers each connected to the RF signal input via a switch; a multi-phase local oscillator signal generator configured to provide a switching signal to each switch; and a summing module configured to receive output signals from each of the IF amplifiers and to provide a second plurality of output IF signals from a weighted sum of the IF amplifier output signals, wherein the second plurality is different to the first plurality.
摘要:
A signal processing arrangement comprises a series of latches (XDL, L1, L2) arranged as a clocked delay line (CDL) having a data input and a data output that are coupled to each other so as to form an inverting loop. An enable circuit (ACDL) allows or prevents a latch (L2) in the series of latches from changing state depending on whether, one clock cycle ago, the latch concerned received a given binary value or the inverse of that given binary 5 value, respectively, from the preceding latch (L1) in the series of latches. Such a circuit configuration allows a low-cost frequency division by an odd number with relatively small duty cycle errors.
摘要:
A device for receiving a RF signal (1; 21) with loop-through output (16) is provided. The device comprises: an input (3) receiving a RF input signal (2); an analog-digital converter (8) converting the RF input signal (2) to a digital signal (9); a digital signal processing unit (10) digitally processing the digital signal (9); a digital-analog converter (14) converting the processed digital signal (13) to a loop-through RF signal (15) corresponding to the RF input signal (2); and a loop-through output (16) outputting the loop-through RF signal (15).
摘要:
The invention relates to frequency conversion systems, in particular for use as up-converters or down-converters in radiofrequency (RF) receivers or transmitters, exemplary embodiments including a radiofrequency receiver (1000) comprising: an RF signal input (1001); a mixing module (1002) comprising a first plurality of IF amplifiers (10041-3) each connected to the RF signal input (1001) via a switch (10031-3); a multi-phase local oscillator signal generator (1300) configured to provide a switching signal to each switch (10031-3); and a summing module (1005) configured to receive output signals from each of the IF amplifiers (10041-3) and to provide a second plurality of output IF signals from a weighted sum of the IF amplifier output signals, wherein the second plurality is different to the first plurality.
摘要:
The invention relates to a digital signal generator for providing one or more phases of a local oscillator signal for use in digital to analogue converters and harmonic rejection mixers. Embodiments disclosed include a local oscillator signal generator (200) for a mixer of a radiofrequency receiver, the signal generator (200) comprising a bit sequence generator (201) having a plurality of parallel output lines (203), a digital signal generator (202) having a serial output line (204) and a plurality of input lines connected to respective output lines (203) of the bit sequence generator (201) and a clock signal input line (205), wherein the digital signal generator (202) is configured to provide an output bit sequence on the serial output line (204) at a rate given by a clock signal provided on the clock signal input line (205) and a sequence given by a sequence of bits from the bit sequence generator (201) on the plurality of input lines (203).
摘要:
An optical disk system includes at least one photo detector connected with a variable gain amplifier, a slicer, and a generator which is in the feedback path between the slicer and amplifier. A differential time delay detector provides the output of the optical disk system. The generator is configured for controlling the amplifier non-linearly so that time constants of the control loop of the amplifier which depend upon the level of the input signals are compensated and the timing behavior of the control loop of the amplifier has a more continuous character. A capacitor forms part of an integrator for making the mean value of the output voltage signal of the slicer equal to zero.
摘要:
A signal processing arrangement comprises an amplifier (AMP V1) that includes a stage with complementary transistors (MP3, MN3) of opposite conductivity type arranged in series between two supply lines (+, −). A controllable biasing circuit (CCS) is provided for changing a quiescent operating point of the stage as a function of a control signal (CS). A control arrangement measures an even order 5 distortion of the amplifier (AMP V1) and adjusts the control signal (CS) so that the even order distortion is below a critical level.
摘要:
A gain-controllable stage (CLN, A1, A2 . . . , A7, ACC) comprises a reactive signal divider (CLN) followed by an amplifier arrangement (A1, A2 . . . , A7, ACC). The reactive signal divider (CLN) may be in the form of, for example, a capacitive ladder network. The gain-controllable stage (CLN, A1, A2 . . . , A7, ACC) has a gain factor that depends on a signal division factor that the reactive signal divider (CLN) provides. The reactive signal divider (CLN) forms part of a filter (LC). The signal division factor is adjusted on the basis of a frequency (F) to which the receiver is tuned and a signal-strength indication (RS).