Abstract:
Millimeter wave (mmWave) technology, apparatuses, and methods that relate to transceivers, receivers, and antenna structures for wireless communications are described. The various aspects include co-located millimeter wave (mmWave) and near-field communication (NFC) antennas, scalable phased array radio transceiver architecture (SPARTA), phased array distributed communication system with MIMO support and phase noise synchronization over a single coax cable, communicating RF signals over cable (RFoC) in a distributed phased array communication system, clock noise leakage reduction, IF-to-RF companion chip for backwards and forwards compatibility and modularity, on-package matching networks, 5G scalable receiver (Rx) architecture, among others.
Abstract:
An Analog-to-Digital Converter, ADC, system is provided. The ADC system comprises a plurality of ADC circuits and a first input for receiving a transmit signal of a transceiver. One ADC circuit of the plurality of ADC circuits is coupled to the first input and configured to provide first digital data based on the transmit signal. The ADC system further comprises a second input for receiving a receive signal of the transceiver. The other ADC circuits of the plurality of ADC circuits are coupled to the second input, wherein the other ADC circuits of the plurality of ADC circuits are time-interleaved and configured to provide second digital data based on the receive signal. Additionally, the ADC system comprises a first output configured to output digital feedback data based on the first digital data, and a second output configured to output digital receive data based on the second digital data.
Abstract:
An apparatus and method for analog-to-digital conversion. The apparatus includes a first analog-to-digital converter (ADC), a second ADC, and a calibration unit. The first ADC is configured to sample an input analog signal at a first sampling frequency. The second ADC is configured to sample the input analog signal at a second sampling frequency. The second sampling frequency is a fraction of the first sampling frequency. The calibration unit is configured to correct a distortion incurred in an output of the first ADC based on an output of the second ADC. The first ADC may be a time-interleaved ADC. The second ADC may be an extra sub-ADC of the time-interleaved ADC. The second ADC may be configured to sample the input analog signal at random sampling phases. A dithering noise may be added to the input analog signal of the second ADC. The calibration unit may be a non-linear equalizer.
Abstract:
Maximum likelihood bit-stream generation and detection techniques are provided using the M-algorithm and Infinite Impulse Response (IIR) filtering. The M-Algorithm is applied to a target input signal X to perform Maximum Likelihood Sequence Estimation on the target input signal X to produce a digital bit stream B, such that after filtering by an IIR filter, the produced digital stream Y produces an error signal satisfying one or more predefined requirements. The predefined requirements comprise, for example, a substantially minimum error. In an exemplary bit detection implementation, the target input signal X comprises an observed analog signal and the produced digital stream Y comprises a digitized output of a receive channel corresponding to a transmitted bit stream. In an exemplary bit stream generation implementation, the target input signal X comprises a desired transmit signal and the produced digital stream Y comprises an estimate of the desired transmit signal.
Abstract:
A signal processing circuit arrangement may include a preamplifier circuit configured to map a first dimension input and a second dimension input to a first subset of a plurality of lookup table coefficients of a two-dimensional (2D) lookup table, wherein the first dimension input and the second dimension input each represent a signal level of one or more input signals, extrapolate from the first subset of the plurality of lookup table coefficients to generate a lookup table output, and apply the lookup table output to the one or more input signals to generate a predistorted input signal for an amplifier.
Abstract:
A digital processor, such as a vector processor or a scalar processor, is provided having an instruction set with a complex angle function. A complex angle is evaluated for an input value, x, by obtaining one or more complex angle software instructions having the input value, x, as an input; in response to at least one of the complex angle software instructions, performing the following steps: invoking at least one complex angle functional unit that implements the one or more complex angle software instructions to apply the complex angle function to the input value, x; and generating an output corresponding to the complex angle of the input value, x, using one or more multipliers of a Multiply Accumulate (MAC) unit of the digital processor, wherein the complex angle software instruction is part of an instruction set of the digital signal processor. Multiplication operations optionally employ one or more multipliers of the MAC unit of the digital processor.
Abstract:
Methods and apparatus are provided for direct synthesis of RF signals using maximum likelihood sequence estimation. An RF digital RF input signal is synthesized by performing maximum likelihood sequence estimation on the digital RF input signal to produce a digital stream, such that after filtering by a prototype filter the produced digital stream produces a substantially minimum error. The substantially minimum error comprises a difference between a digital output of the prototype filter and the digital RF input signal. The digital stream is substantially equal to the input digital RF signal. The digital stream can be applied to an analog restitution filter, and the output of the analog restitution filter comprises an analog RF signal that approximates the digital RF input signal.
Abstract:
A digital processor is provided having an instruction set with a complex exponential function. The digital processor evaluates a complex exponential function for an input value, x, by obtaining a complex exponential software instruction having the input value, x, as an input; and in response to the complex exponential software instruction: invoking at least one complex exponential functional unit that implements complex exponential software instructions to apply the complex exponential function to the input value, x; and generating an output corresponding to the complex exponential of the input value, x. A complex exponential function for an input value, x, can be evaluated by wrapping the input value to maintain a given range; computing a coarse approximation angle using a look-up table; scaling the coarse approximation angle to obtain an angle from 0 to θ; and computing a fine corrective value using a polynomial approximation.
Abstract:
A signal processing circuit arrangement may include a preamplifier circuit configured to map a first dimension input and a second dimension input to a first subset of a plurality of lookup table coefficients of a two-dimensional (2D) lookup table, wherein the first dimension input and the second dimension input each represent a signal level of one or more input signals, extrapolate from the first subset of the plurality of lookup table coefficients to generate a lookup table output, and apply the lookup table output to the one or more input signals to generate a predistorted input signal for an amplifier.
Abstract:
Methods and apparatus are provided for direct synthesis of RF signals using maximum likelihood sequence estimation. An RF digital RF input signal is synthesized by performing maximum likelihood sequence estimation on the digital RF input signal to produce a digital stream, such that after filtering by a prototype filter the produced digital stream produces a substantially minimum error. The substantially minimum error comprises a difference between a digital output of the prototype filter and the digital RF input signal. The digital stream is substantially equal to the input digital RF signal. The digital stream can be applied to an analog restitution filter, and the output of the analog restitution filter comprises an analog RF signal that approximates the digital RF input signal.