Techniques associated with link establishment in a fronthaul network are described herein. In one embodiment, a method includes receiving, by a proxy node, a Common Public Radio Interface (CPRI) bit stream transmitted by a radio equipment controller, wherein the CPRI bit stream is transmitted within a transmit time interval of the radio equipment controller; and fast-sampling, by the proxy node, the CPRI bit stream to determine whether a hyper frame number synchronization with the radio equipment controller at a common matching link bit rate is achievable, wherein the fast-sampling comprises attempting to decode the received CPRI bit stream and achieve the hyper frame number synchronization for each of a plurality of link bit rates configured for a fast-sampling time period during at least one fast-sampling time interval configured for the proxy node.

Techniques that provide link establishment between a radio equipment controller (REC) and a radio equipment (RE) in a fronthaul network are described herein. In one embodiment, a method includes performing, Common Public Radio Interface (CPRI) Layer 1 (L1) link auto-negotiation operations to establish a CPRI link between the REC and RE. A proxy slave may achieve a hyper frame number (HFN) synchronization with the REC at a link bit rate for a first CPRI bit stream and communicate the first CPRI bit stream and the link bit rate to a proxy master. The proxy master may communicate a second CPRI bit stream to the proxy slave to transmit to the REC. The L1 link auto-negotiation operations are completed and CPRI link is established between the REC and the RE when the REC achieves a HFN synchronization for the second CPRI bit stream.

A symbol rate determination method for determining a symbol rate of an input signal is disclosed. The method comprises: receiving the input signal; determining respective pulse widths of pulses contained in the input signal; allocating the pulse widths to groups based on a magnitude of the respective pulse widths; determining a group pulse width for each of the groups, the group pulse width being representative of the pulse widths contained in the respective group; and determining the symbol rate based on the determined group pulse widths. Moreover, a measurement instrument for determining a symbol rate of an input signal is disclosed.

A bit rate estimation apparatus used for estimation of a bit rate, BR, of a digital signal, DS, the bit rate estimation apparatus comprising a data processing unit adapted to determine a regularized cepstrum, CEP, of the digital signal; a peak identification unit adapted to identify a significant peak within the regularized cepstrum, CEP, determined by the data processing unit; and a bit rate determination unit adapted to determine the bit rate of the digital signal, DS, based on the significant peak identified by the peak identification unit.

A device includes a transmitter coupled to a node, where the node is to couple to a wired link. The transmitter has a plurality of modes of operation including a calibration mode in which a range of communication data rates over the wired link is determined in accordance with a voltage margin corresponding to the wired link at a predetermined error rate. The range of communication data rates includes a maximum data rate, which can be a non-integer multiple of an initial data rate.

A user equipment (UE) may receive, during a first transmission time interval (TTI), one or more broadcasts from a base station over a first frequency range. The UE may receive, during the first TTI, a reference signal over a second frequency range that is disjoint from the first frequency range. The UE may receive, during a subsequent TTI, a downlink grant from the base station scheduling a downlink data transmission over at least portions of both the first frequency range and the second frequency range, wherein the downlink grant comprises a reference signal sharing indication. The UE may obtain a channel estimate for the second frequency range of the subsequent TTI based at least in part on the reference signal and may refrain from applying the channel estimate to the first frequency range in the subsequent TTI.

A method can be used for transmission of at least one packet of at least one bit over a serial link capable of taking two different states respectively associated with the two possible logical values of the at least one transmitted bit. Starting from a transmission start time of the at least one bit and up to the expiration of a first portion of a bit time associated with the at least one bit, the link is placed in one of its states depending on the logical value of the at least one bit. Upon the expiration of the first portion of this bit time, a first additional transition is generated over the link so as to place the link in its other state up to the expiration of the bit time.

A bandwidth detection device comprises a receiving circuit, for receiving a first plurality of frequency-domain signals on a first subchannel; a filter circuit, coupled to the receiving circuit, for transferring the first plurality of frequency-domain signals to a first plurality of filtered frequency-domain signals according to a filter function; and a processing circuit, coupled to the filter circuit, for comparing the first plurality of frequency-domain signals with the first plurality of filtered frequency-domain signals, to determine whether the first subchannel comprises first transmitted data.

The present disclosure relates to a circuit for calibrating a baud rate. The circuit includes: a first counter connected to a receiving module of a serial port chip and configured to record a first low level duration of a data frame received by the receiving module; a second counter configured to: receive a bit sampling pulse generated from sampling the data frame according to a current baud rate of the receiving module, and record a quantity of the bit sampling pulse in the first low level duration; a divider, connected to the first counter and the second counter and calculate a calibration baud rate according to the first low level duration and the quantity of the bit sampling pulse in the first low level duration; and a selector, connected to the receiving module and the divider and configured to output the calibration baud rate to the receiving module.

A device includes a first interface to receive a signal from a first communication link, wherein the receive signal includes out-of-band (OOB) information. A detector coupled to the first interface detects the OOB information. An encoder coupled to the detector encodes the OOB information into one or more symbols (e.g., control characters). A second interface is coupled to the encoder and a second communication link (e.g., a serial transport path). The second interface transmits the symbols on the second communication link. The device also includes mechanisms for preventing false presence detection of terminating devices.