Embodiments of the invention provide advances in liquid-crystal technology for use as tunable phase-delay lines. The amount of phase delay through the liquid crystal is adaptively tuned, in order to coherently combine two signals, regardless of their phase differences. By adaptively adjusting the phase delays in the two signal paths, maximum coherent power combining is ensured. This ability to coherently combine the power of two signals regardless of their initial phase differences can greatly simplify, for example, antenna-diversity techniques used in MIMO applications as well as other applications.

A signal interface unit for a distributed antenna system (DAS) includes a channelized radio carrier interface configured to receive a downlink channelized radio carrier for a radio frequency carrier from a channelized radio carrier base station interface; an antenna side interface configured to communicate a downlink digitized radio frequency signal from the antenna side interface to the DAS communicatively coupled to the antenna side interface; and a signal conversion module communicatively coupled between the channelized radio carrier interface and the antenna side interface and configured to convert between the downlink channelized radio carrier and the downlink digitized radio frequency signal at least in part by adjusting at least one downlink attribute of the downlink digitized radio frequency signal communicated to the DAS based on requirements of the channelized radio carrier base station interface to cause the DAS to appear as a remote radio head to the channelized radio carrier interface.

A method of transmitting information between a plurality of radioelectric stations and an associated transmission network are disclosed. In one aspect, the method transmits information between radioelectric stations, each station including a transmitter and a receiver, the information including NbMot words of data, NbMot being an integer >1. The transmission method includes: determining at least one polynomial of degree NbMot1, each of the NbMot coefficients of the polynomial corresponding to a respective word, the polynomial having an indeterminacy, calculating NbRepet polynomial values for the polynomial, NbRepet being an integer >1, each polynomial value being calculated for a respective predetermined value of the indeterminacy, transmitting the calculated polynomial values from one radioelectric station to at least one other radioelectric station, receiving polynomial values by the other radioelectric station, and determining, via the other radioelectric station, the NbMot words from a Lagrange interpolation of the received polynomial values.

Provided are a synchronization track reference signal transmission processing, receiving processing method and apparatus. According to the transmission processing method, a base station configures, for a new carrier, subframe pattern information used for a synchronization track reference signal (STRS), wherein the subframe pattern information is used for describing at least one subframe for transmitting the STRS in a radio frame; and the base station transmits the configured subframe pattern information to user equipment. By applying the technical solution, the technical problems of being unable to transmit the STRS in a new carrier since there is not technical solution regarding how to transmit the STRS in the related technologies, etc. are solved, thereby achieving the transmission of the STRS in the new carrier.

A method of downlink channel state information (DL CSI) measurement and reporting is proposed in FR1 frequency division duplex (FDD) systems. CSI reference signal (CSI-RS) is directed towards dominant spatial domain (SD, beam) and frequency domain (FD, delay) components in the propagation environment. By partial channel reciprocity, angles and delays in the DL channel can be obtained by UL channel measurement. UE only needs to measure and feedback the DL CSI corresponding to the dominant angles and delays. BS obtains the precoder in the antenna-frequency domain using the CSI feedback in the beam-delay domain. BS uses the precoder for transmission over Physical downlink shared channel (PDSCH). In one embodiment, UE reconstructs the DL channel on a multitude of delays using the DL channel estimated on a few beamformed CSI-RS and delay tap indices signaled from the network.