Qualcomm Incorporated

Nicola Varanese

Christian Pietsch

Juan Montojo

Andrea Garavaglia

Patrick Stupar

Stephen Jay Shellhammer

Christoph A Joetten

Roberto Rimini

Marc W Werner

Georg Frank

Peter Zillmann

Sheng-Yuan Tu

Pierpaolo Vallese

Tienchuan Ko

Stephen J Shellhammer

Aspects of the present disclosure provide methods and apparatus for applying transmitter beamforming for self-interference cancellation. According to aspects, a method generally includes in an acquisition phase, iteratively acquiring received power measurements for different receive chains for transmissions sent via a plurality of beam directions; estimating a self-interference subspace eigenvector based, at least in part, on the received power measurements; based on the estimated self-interference subspace eigenvector, performing a local search of a nullspace to identify a filtering eigenvector; and applying the filtering eigenvector to one or more transmission chains to cancel self-interference on one or more receive chains.

Transmitter beamforming for self-interference cancellation

In aspects, apparatus and methods of wireless communication, and more specifically of improved mitigation of interference caused by a transmitter are provided. For example, in aspects, a method of interference mitigation of wireless communication is provided including transmitting at least one transmit signal from at least one transmit chain of a user equipment (UE) over a wireless medium, receiving a composite signal that includes a desired receive signal transmitted from a device and a distortion signal, generating a modified composite signal by removing at least a portion of the desired receive signal from the composite signal, generating a distortion signal estimate based on the modified composite signal, and canceling the distortion signal estimate from the composite signal. Numerous other aspects are provided.

Mitigation of interference caused by a transmitter

A receiver receives packets without prior knowledge of their bandwidths. The receiver calculates a first auto-correlation function for a first channel, a second auto-correlation function for a second channel, and a dot product of the first auto-correlation function and the second auto-correlation function. A packet is detected and its bandwidth classified based at least in part on the dot product.

Packet detection and bandwidth classification for variable-bandwidth packets

A device may demodulate a set of OFDM data-pilot symbols and select a subset of based at least in part on the position of each data pilot on a constellation map (e.g., how close the data pilot symbol is to an actual constellation point). The device may then perform a data-pilot-based phase estimation based at least in part on the selected subset. The device may also reduce the number of data pilots by partitioning a set of subcarriers into groups and selecting a representative subcarrier from each group. The phase estimation may then be based on the data pilots received on the selected subcarriers. In some cases, the device may also generate a smooth phase signal based on a linear regression algorithm including a phase averaging and a phase offset estimation and perform the phase estimation using the smooth phase signal.

Feed-forward phase tracking

A coax network unit (CNU) is coupled to a coax line terminal (CLT). In first and second modes of operation, the CNU transmits data during an upstream window and receives data during a downstream window. In the first mode of operation, a duration of data transmission for the upstream window or a duration of data reception for the downstream window is reduced by a specified amount with respect to the second mode. A sounding signal is transmitted in the first mode in a probing slot that has a duration corresponding to the specified amount.

Wideband signal generation for channel estimation in time-division-duplexing communication systems

A coax line terminal (CLT) transmits allocations of upstream bandwidth to a plurality of coax network units (CNUs). In response to the allocations, the CLT receives frames with data in a plurality of physical resource blocks that each correspond to a distinct set of subcarriers. The plurality of physical resource blocks includes a first group of physical resource blocks that all have a first constant allowed capacity. Sizes and modulation orders of respective physical resource blocks in the first group vary as defined by a first modulation profile. The data in the first group are received from one or more CNUs that are assigned the first modulation profile.

Constant-capacity physical resource blocks for upstream transmissions over coax

A communication device includes a resource allocation module to allocate coax resources for signals to be transmitted over a cable plant and a coax physical layer device to transmit the signals over the cable plant using the allocated coax resources. The communication device also includes a media access controller, coupled to the multi-point control protocol implementation and the coax physical layer device, to provide to the coax physical layer device a bitstream that includes data for the signals and also includes information specifying the allocated coax resources.

Methods and systems of specifying coaxial resource allocation across a MAC/PHY interface

A network device includes a plurality of physical-media entities (PMEs), each corresponding to a distinct channel, to generate transmit signals based on transmit packets received over a media-independent interface. The network device also includes a channel-bonding sublayer to direct the transmit packets from the media-independent interface to respective PMEs of the plurality of PMEs. The channel-bonding sublayer has a substantially fixed delay between the media-independent interface and the plurality of PMEs for the transmit packets.

Physical-layer channel bonding

A method of registering a coax network unit (CNU) in a network is performed at an optical-coax unit (OCU). In the method, a first discovery message is broadcasted to a plurality of CNUs. In response, a first registration request is received from a first CNU of the plurality of CNUs. In response to the first registration request, a proxy entity corresponding to the first CNU is implemented in the OCU. A second discovery message is received from an optical line terminal (OLT). In response to the second discovery message, a second registration request is transmitted to the OLT requesting registration of the proxy entity with the OLT.

Multi-point control protocol proxy architecture in a network with optical and coaxial domains

An optical-coax unit (OCU) includes an optical PHY to receive and transmit optical signals and a coax PHY to receive and transmit coax signals. The OCU also includes a media-independent interface to provide a first continuous bitstream from the optical PHY to the coax PHY and a second continuous bitstream from the coax PHY to the optical PHY. The first continuous bitstream corresponds to received optical signals and transmitted coax signals, and the second continuous bitstream corresponds to received coax signals and transmitted optical signals.

Repeater fiber-coax units

A media converter is to be coupled to an optical line terminal via an optical link and to a plurality of coax network units via coax links in a cable plant. The media converter includes an optical physical-layer device to receive and transmit optical signals via the optical link and a coax physical-layer device to receive and transmit electrical signals via the coax links. The media converter also includes an implementation of an optical-coax convergence layer to schedule transmissions of electrical signals from the plurality of coax network units by allocating coax resources among the plurality of coax network units in accordance with resource allocation for the optical link.

Methods and systems for allocating resources in a network with optical and coaxial components

A physical-layer device includes a first sublayer to receive a first continuous bitstream from a media-independent interface and to provide a second continuous bitstream to the media-independent interface. The physical-layer device also includes a second sublayer to transmit first signals corresponding to the first continuous bitstream onto an external link during a first plurality of time windows and to receive second signals corresponding to the second continuous bitstream from the external link during a second plurality of time windows. The second plurality of time windows is distinct from the first plurality of time windows.

Methods and systems for implementing time-division duplexing in the physical layer

Successive pairs of OFDM symbols are transmitted by an OFDM transmitter and received by an OFDM receiver. The successive pairs include a first pair of OFDM symbols. First and second OFDM symbols of the first pair both include pilot symbols on two subcarriers that are symmetric about a center carrier frequency. The two subcarriers are the same for the first and second OFDM symbols. The pilot symbols on the two subcarriers for the first and second OFDM symbols compose an orthogonal matrix. The OFDM receiver estimates frequency responses at frequencies including the frequencies of the two subcarriers and compensates for signal impairment based at least in part on the estimated frequency responses.

Paired OFDM pilot symbols

A receiver receives a repeating or periodic signal and, based on the signal, estimates a carrier frequency offset for the receiver. Based on the signal and the estimated carrier offset, an I/Q mismatch for the receiver is estimated and compensation for the estimated I/Q mismatch is performed. After compensating for the estimated receiver I/Q mismatch, the carrier frequency offset is re-estimated.

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Nuremberg, Germany

Nicola Varanese