A user equipment (UE) for channel estimation in a high-speed single-frequency network (HS-SFN) is provided. The UE includes at least one non-transitory computer-readable medium; and at least one processor, which, when executing instructions stored on the at least one non-transitory computer-readable medium, causes the UE to perform a method including calculating an estimated frequency offset (FO) correction for a received signal using at least an FO estimation generated by an automatic frequency control (AFC) module using at least a previously-calculated channel estimate output from a channel estimator (CE) as input in a first feedback loop; and calculating, by the CE, a current channel estimate using at least the received signal adjusted by the estimated FO correction from the first feedback loop and one or more channel parameter estimates generated by the AFC using at least the previously-calculated channel estimate output from the CE as input in a second feedback loop.

Receivers including estimation unit (EU) circuits and related processing techniques for wireless systems are provided. Efficient expressions for quadrature amplitude modulation (QAM) symbol mean and variance calculations are utilized with efficient expressions and implementations that are adaptive to different orders of QAM formats. An EU circuit includes a mean estimation unit (MEU) circuit and/or second moment estimation unit (SEU) circuit. Each estimation unit circuit is configured to receive a variable QAM normalization factor so that the circuit can be adapted to different QAM orders. Each MEU or SEU circuit can be configured for sequential and/or parallel processing. A pool including multiple MEU circuits and/or a pool including multiple SEU circuits is provided in one embodiment, with a control unit for configuring and reconfiguring the pools of circuits for mean and variance estimation for data streams of QAM symbols.

A receiver (e.g., for a 10 G fiber communications link) includes an interleaved ADC coupled to a multi-channel equalizer that can provide different equalization for different ADC channels within the interleaved ADC. That is, the multi-channel equalizer can compensate for channel-dependent impairments. In one approach, the multi-channel equalizer is a feedforward equalizer (FFE) coupled to a Viterbi decorder, for example, a sliding block Viterbi decoder (SBVD); and the FFE and/or the channel estimator for the Viterbi decoder are adapted using the LMS algorithm.

A method, network node and wireless transceiver, for implementing iterative downlink passive intermodulation (PIM) spatial avoidance algorithms are provided. According to one aspect, a method in a wireless transceiver includes determining an uplink signal power. The method also includes determining an estimate of a downlink PIM subspace that minimizes a cost function that depends on the uplink signal power and a previous estimate of the downlink PIM subspace. The method further includes applying a correction to a downlink antenna signal to reduce the PIM, the correction being based at least in part on the estimate of the downlink PIM subspace

According to various examples, communication device is described comprising a receiver configured to receive a signal from another communication device via a radio channel and a processor configured to estimate a power delay profile of the radio channel by maximum likelihood estimation of the power delay profile from the received signal and perform receive signal processing in accordance with the estimated power delay profile.

A receiver (e.g., for a 10G fiber communications link) includes an interleaved ADC coupled to a multi-channel equalizer that can provide different equalization for different ADC channels within the interleaved ADC. That is, the multi-channel equalizer can compensate for channel-dependent impairments. In one approach, the multi-channel equalizer is a feedforward equalizer (FFE) coupled to a Viterbi decoder, for example a sliding block Viterbi decoder (SBVD); and the FFE and/or the channel estimator for the Viterbi decoder are adapted using the LMS algorithm.

Apparatuses (and methods of manufacturing same), systems, and methods for channel interpolation/estimation and/or frequency tracking suitable for a receiver in a high speed single frequency network (HS-SFN) scenario are described. In one aspect, an estimated frequency offset (FO) correction is calculated for a received signal using at least an FO estimation provided by an automatic frequency control (AFC) in a first feedback loop and a channel estimate is calculated using at least the estimated FO and one or more channel parameter estimates from the AFC in a second feedback loop. In another aspect, a phase locked loop (PLL) receives an lth orthogonal frequency division multiplexing (OFDM) symbol and produces a per-tap phase value for each tap i of the lth OFDM symbol. The per-tap phase values of the lth OFDM symbol are used to generate the PLL output, which is also used as input to a feedback loop.

A Least Mean Squares (LMS) polynomial estimator is disclosed. The LMS polynomial estimator may be a LMS moving window polynomial estimator capable of performing real-time polynomial estimation and evaluation of successive time derivatives of a function of a single variable up to a specified polynomial order. The estimator makes a unique use system memory that allows for the evaluation of the least squares normal equations with a very low computational footprint. This allows the estimator to be realizable in computationally-constrained environments such as embedded systems. The LMS polynomial estimator may be implemented in a frequency estimator for estimation of the phase, frequency, Doppler, delta Doppler, and/or higher order time derivatives of phase. Estimates may be performed in real time, running at the same rate as the inbound signal.

The present application describes a self-interference channel estimation system. The system includes a signal generator configured to generate a swept tone having a frequency ranging from an upper edge of a reception band to a lower edge of the reception band, and configured to generate a message signal. The system includes an infinite impulse response (IIR) filter configured to determine an infinite impulse response of a self-interference channel based upon the swept tone. The system includes a processor configured to characterize the self-interference channel based upon the infinite impulse response.

Techniques to manage dwell times for pilot rotation are described. An apparatus may comprise a memory configured to store a data structure with a set of modulation and coding schemes (MCS) available to an orthogonal frequency division multiplexing (OFDM) system, each MCS having an associated pilot dwell time. The apparatus may further comprise a processor circuit coupled to the memory, the processor circuit configured to identify a MCS to communicate a packet using multiple subcarriers of the OFDM system, and retrieve a pilot dwell time associated with the MCS from the memory, the pilot dwell time to indicate when to shift a pilot tone between subcarriers of the multiple subcarriers during communication of the packet. Other embodiments are described and claimed.