Abstract: A partial response decision feedback equalizer (PrDFE) includes a receiver including at least first and second comparators operative to compare an input signal representing a sequence of symbols against respective thresholds and to respectively generate first and second receiver outputs. A first selection stage is provided to select (a) between the first comparator output and a first resolved symbol according to a first timing signal, and (b) between the second comparator output and the first resolved symbol according to the first timing signal, to produce respective first and second selection outputs. A second selection stage selects between the first and second selection outputs according to a selection signal. The selection signal is dependent on a prior resolved symbol that precedes the first resolved symbol in the sequence.

Abstract: Embodiments of a circuit are described. In this circuit, a modulation circuit provides a first modulated electrical signal and a second modulated electrical signal, where a given modulated electrical signal, which can be either the first modulated electrical signal or the second modulated electrical signal, includes minimum-shift keying (MSK) modulated data. Moreover, a first phase-adjustment element, which is coupled to the modulation circuit, sets a relative phase between the first modulated electrical signal and the second modulated electrical signal based on a phase value of the first phase-adjustment element. Additionally, an output interface, which is coupled to the first phase-adjustment element, is coupled to one or more antenna elements which output signals. These signals include a quadrature phase-shift-keying (QPSK) signal corresponding to the first modulated electrical signal and the second modulated electrical signal.

Abstract: A data encoding scheme for transmission of data from one circuit to another circuit considers the Hamming Weight of combined multiple words to determine whether to invert or not invert an individual word to be transmitted. The multi-word data encoding scheme performs DBI encoding with data inversion conducted based on the total HW in the combined multiple words. The decision to invert or not invert each of the multiple words is made based on the sum of the individual Hamming Weights of each of the words. Such encoding has the advantage that SSO noise is dramatically reduced when the encoded data has a large number of words transmitted from one circuit to another circuit over a wide parallel bus.

Abstract: Embodiments of a communication circuit are described. This communication circuit includes an input node (212) to receive a set of data symbols and a partitioner (216) coupled to the input node. The partitioner is to divide the set of data symbols into M irregular subgroups of data symbols, a given one of which includes non-consecutive data symbols in the set of data symbols. Moreover, this given irregular subgroup of data symbols includes at least two pairs of adjacent data symbols having different inter-data-symbol spacings in the set of data symbols. This communication circuit also includes M modulators (218-1, 218-N1) coupled to the partitioner, where the given irregular subgroup of data symbols is coupled to a given modulator in the M modulators. Furthermore, the communication circuit includes M output nodes, where a given output node in the M output nodes is coupled to the given modulator and is to couple to an antenna element in M antenna elements (226).

Abstract: A circuit, wherein an encoder circuit encodes a set of N symbols as a given codeword in a code space, where the given codeword includes a set of M symbols. M drivers are coupled to the encoder circuit and are coupled to M links in a channel, where a given driver outputs a given symbol in the set of M symbols onto a given link. An error-detection circuit coupled to the encoder circuit generates and stores error-detection information associated with the set of M symbols, facilitating subsequent probabilistic determination of a type of error during communication of the set of M symbols to another circuit. A receiver circuit receives feedback information from the other circuit, which includes error information about detection of another type of error in the set of M symbols based on characteristics of the code space. Control logic performs remedial action based on the feedback information.

Abstract: A data encoding scheme for transmission of data from one circuit to another circuit combines DBI encoding and non-DBI encoding and uses a data mask signal to indicate the type of encoding used. The data mask signal in a first state indicates that the data transmitted from one circuit to said another circuit is to be ignored, and the data mask signal in a second state indicates that the data transmitted from one circuit to said another circuit is not to be ignored. If the data mask signal is in the second state, a first subset of the data is encoded with data bus inversion and a second subset of the data is encoded differently from data bus inversion. Such encoding has the advantage that SSO noise is dramatically reduced when the encoded data is transmitted from one circuit to another circuit.

Abstract: A data system 102 permits bus encoding based on frequency of the bus; an encoding scheme may be implemented to avoid undesirable frequency conditions such as a resonant condition that may lead to degradation in system performance. The device or integrated circuit will typically include an encoder; in one embodiment, the encoder is a data bus inversion (DBI) circuit that selectively inverts all lines of a data bus. A detector that may include a band-pass or stop-band filter that, for example, evaluates data for transmission on the bus to detect frequency, for example, a predetermined frequency or a frequency range. The detector provides a control signal for the encoder to selectively apply an encoding scheme as a function of frequency.

Abstract: Embodiments in the present disclosure pertain to a multi-antenna beam-forming system for transmitting constant envelope signals decomposed from a variable envelope signal. The variable envelope signal is decomposed into two constant envelope signals. Each of the constant envelope signals are separately amplified by power amplifiers and transmitted over separate antennas. Beam steering delays can be added to the transmit paths of the constant envelope signals to direct the beam to the location of a receiver. The transmitted constant envelope signals combine through spatial out-phasing such that a receiving antenna receives a variable envelope signal.

Abstract: Described are digital communication systems that transmit and receive parallel sets of data symbols. Differences between successive sets of symbols induce changes in the current used to express the symbol sets, and thus introduce supply ripple. A receiver adds compensation current to reduce supply ripple. The compensation current is calculated based upon prior data samples rather than the current symbols, and consequently increases the maximum instantaneous current fluctuations between adjacent symbol sets as compared with circuits that do not include the compensation. The frequency response of the power-distribution network filters out the increased data dependence of the local supply current, however, and consequently reduces the fluctuations of total supply current. Some embodiments provide compensation currents for both transmitted and received symbols.

Abstract: Embodiments of a circuit are described. In this circuit, an encoder circuit encodes a set of N symbols as a given codeword in a code space, where the given codeword includes a set of M symbols. M drivers are coupled to the encoder circuit and are coupled to M links in a channel, where a given driver outputs a given symbol in the set of M symbols onto a given link. Moreover, an error-detection circuit, which is coupled to the encoder circuit, generates and stores error-detection information associated with the set of M symbols, where the error-detection information facilitates subsequent probabilistic determination of a type of error during communication of the set of M symbols to another circuit. Additionally, a receiver circuit receives feedback information from the other circuit. This feedback information includes error information about detection of another type of error in the set of M symbols based on characteristics of the code space.

Abstract: Encoder and decoder circuits that encode and decode a series of data words to/from a series of code words. The data words include L symbols. The code words include M symbols, where M is larger than L. A set of tightly coupled M links to convey respective symbols in each of the series of code words. The code words are selected such that between every two consecutive code words in a series of code words, an equal number of transitions from low to high and high to low occur on a subset of the M-links.

Abstract: A multi-phase partial response equalizer circuit includes sampler circuits that sample an input signal to generate sampled signals in response to sampling clock signals having different phases. A first multiplexer circuit selects one of the sampled signals as a first sampled bit to represent the input signal. A first storage circuit coupled to an output of the first multiplexer circuit stores the first sampled bit in response to a first clock signal. A second multiplexer circuit selects one of the sampled signals as a second sampled bit to represent the input signal based on the first sampled bit. A second storage circuit stores a sampled bit selected from the sampled signals in response to a second clock signal. A time period between the second storage circuit storing a sampled bit and the first storage circuit storing the first sampled bit is substantially greater than a unit interval in the input signal.

Abstract: Embodiments of an encoder and a decoder are described. The encoder encodes data into a series of parallel codewords. Each codeword is expressed two sets of logic values (e.g., a set of logic 0s and a set of logic 1s) on two corresponding sets of output nodes, a first set and a second set. The encoder selects a current codeword such that it differs from the immediately preceding codeword by a fixed number of zero-to-one transitions on the first set of nodes and a fixed number of one-to-zero transitions on the second set of nodes. A decoder receives and decodes the codewords by comparing symbols on node pairs for which the symbols expressed in the prior code word were alike and decoding the results of those comparisons.

Abstract: A multi-mode transmitter within an integrated circuit device. The multi-mode transmitter transmits a first data sequence in a baseband signal when a first transmission mode is enabled, and transmits the first data sequence in a multi-band signal when a second transmission mode is enabled.

Abstract: A data encoding scheme for transmission of data from one circuit to another circuit considers the Hamming Weight of combined multiple words to determine whether to invert or not invert an individual word to be transmitted. The multi-word data encoding scheme performs DBI encoding with data inversion conducted based on the total HW in the combined multiple words. The decision to invert or not invert each of the multiple words is made based on the sum of the individual Hamming Weights of each of the words. Such encoding has the advantage that SSO noise is dramatically reduced when the encoded data has a large number of words transmitted from one circuit to another circuit over a wide parallel bus.

Abstract: A data receiver circuit includes an interface to receive an input signal that includes a data signal and a clock signal superimposed on the data signal. The data signal has an associated symbol rate and an associated symbol period equal to the reciprocal of the associated symbol rate. The clock signal has a frequency N times the associated symbol rate, where N is an integer. A phase-locked loop (PLL) coupled to the interface extracts the clock signal from the input signal to provide an extracted clock signal. A phase interpolator adjusts the phase of the extracted clock signal to provide a phase-adjusted extracted clock signal. A sampling circuit samples the data signal at a sampling point. The sampling circuit is synchronized to the phase-adjusted extracted clock signal.

Abstract: M-bit data are encoded into n-bit data such that the encoded n-bit data has a sufficient number of encoded data patterns enough to encode the number (2m) of data patterns in the m-bit data but that the n-bit data has Hamming Weights (HWs) with minimum (smallest possible) variation. Specifically, encoder logic is configured to receive 2m of m-bit data patterns and encode the 2m of m-bit data patterns to n-bit encoded data patterns, n being greater than m and me being a positive integer greater than one. The encoder logic is configured to map the 2m m-bit data patterns to a subset of 2m of the n-bit encoded data patterns, and the n-bit data patterns in said subset has a minimum (smallest possible) range of Hamming Weight variation while the number of the n-bit data patterns in said subset is not less than 2m.

Abstract: Embodiments of a circuit are described. In this circuit, a transmit circuit provides signals to antenna elements during an acquisition mode, where a given signal to a given antenna element includes at least two frequency components having associated phases, and where the phase of a given frequency component in the given signal is different from phases of the given frequency component for the other antenna elements. Moreover, an output node couples the transmit circuit to the antenna elements that transmit the signals. Note that these signals establish an angle of a communication path between the circuit and another circuit.

Abstract: A receiver includes an amplifier and a transconductance bias circuit. The amplifier gain is largely determined by transconductance and load impedance. The transconductance bias circuit varies the transconductance in inverse proportion to the load impedance to maintain the gain over process, voltage, and temperature. Differential amplifiers can use separate transconductance bias circuits for each amplifier leg, and the bias circuits can be independently controlled to minimize common-mode gain and voltage offsets.

Abstract: A data encoding scheme for transmission of data from one circuit to another circuit combines DBI encoding and non-DBI encoding and uses a data mask signal to indicate the type of encoding used. The data mask signal in a first state indicates that the data transmitted from one circuit to said another circuit is to be ignored, and the data mask signal in a second state indicates that the data transmitted from one circuit to said another circuit is not to be ignored. If the data mask signal is in the second state, a first subset of the data is encoded with data bus inversion and a second subset of the data is encoded differently from data bus inversion. Such encoding has the advantage that SSO noise is dramatically reduced when the encoded data is transmitted from one circuit to another circuit.