241 results about "Remote radio head" patented technology

A remote radio head unit (RRU) system for achieving high efficiency and high linearity in wideband communication systems is disclosed. The present invention is based on the method of adaptive digital predistortion to linearize a power amplifier inside the RRU. The power amplifier characteristics such as variation of linearity and asymmetric distortion of the amplifier output signal are monitored by a wideband feedback path and controlled by the adaptation algorithm in a digital module. Therefore, embodiments of the present invention can compensate for the nonlinearities as well as memory effects of the power amplifier systems and also improve performance, in terms of power added efficiency, adjacent channel leakage ratio and peak-to-average power ratio. The present disclosure enables a power amplifier system to be field reconfigurable and support multi-modulation schemes (modulation agnostic), multi-carriers, multi-frequency bands and multi-channels. As a result, the remote radio head system is particularly suitable for wireless transmission systems, such as base-stations, repeaters, and indoor signal coverage systems.

A method and apparatus are provided for selecting transmission parameters for multiple transmit antenna arrays. In one embodiment, the invention includes receiving a signal from a remote radio, measuring the transmit coherency of the received signal, selecting, based on the transmit coherency, whether to apply coherent combining to signals transmitted to the remote radio using each of two transmit antenna arrays to each form a beam to coherently combine with each other beam upon receipt by the remote radio, selecting, based on the transmit coherency, whether to apply transmit diversity to signals transmitted to the remote radio using each of the two transmit antenna arrays as diversity antennas. The embodiment further includes determining signal transmission parameters to apply to the two antenna arrays for transmissions to the remote radio based on the selections, and transmitting a signal to the remote radio from the two transmit antenna arrays by applying the determined signal transmission parameters to the two transmit antenna arrays.

A remote radio head unit (RRU) system for multiple operating frequency bands, multi-channels, driven by a single or more wide band power amplifiers. More specifically, the present invention enables multiple-bands RRU to use fewer power amplifers in order to reduce size and cost of the multi-band RRU. The present invention is based on the method of using duplexers and / or interference cancellation system technique to increase the isolation between the transmitter signal and receiver signal of the RRU.

A remote radio head unit (RRU) system for multiple operating frequency bands, multi-channels, driven by a single or more wide band power amplifiers. More specifically, the present invention enables multiple-bands RRU to use fewer power amplifiers in order to reduce size and cost of the multi-band RRU. The present invention is based on the method of using duplexers and / or interference cancellation system technique to increase the isolation between the transmitter signal and receiver signal of the RRU.

The invention relates to a method for transmitting a plurality of antenna signals in a wireless Base Transceiver Station (BTS) using Remote Radio Head (RRH) technology and the corresponding system. The method includes the steps of: transmitting signals over the transmit channel using Synchronous Digital Hierarchy (SDH) / Optical Transmission Network (OTN), multiplexing the plurality of antenna signals adopting the manners of time division multiplex or GFP frame-level multiplex; forming the multiplexed antenna signal stream and in-band control signaling stream into Generic Framing Procedure (GFP) frame; or forming the plurality of antenna signals and the plurality of respective control signals on the in-band control signaling channel into a plurality of respective GFP frames in parallel; and further mapping the GFP frames to STM-N / OTM-n frames, therefore multiplexing the plurality of antenna signals and the in-band control signaling stream to realize the SDH / OTN-based transmission. According to the invention, in the circumstance of using a plurality of antennas for transmitting signals, the strict time and phase relations between various antenna signals can be ensured, and also system complexity can be simplified, the transmission delays from various antenna signals to CBTS are totally the same.

Delay measurement and delay calibration methods and apparatus are described for use within distributed wireless base stations employing a remote radio head topology. The methods and apparatus are usable in any system that requires accurate delay measurement and / or constant delay through an electronic device. The methods and apparatus for measuring delay embody a highly accurate distributed delay measurement architecture that handles multiple delay paths within distributed wireless base stations employing a remote radio head topology. The method and apparatus are amenable to implementation with current integrated circuit technology. The methods and apparatus for calibrating electronic delay within distributed base stations employing a remote radio head topology are useful for implementing distributed wireless base stations where transmit diversity is desired. Using the methods disclosed herein, delay within a distributed wireless base station can be measured and calibrated to achieve very deterministic delay characteristics at the system level.

The present invention discloses a method for transmitting signal between a central channel processing Main Unit (MU) and one or more Remote Radio Units (RRUs) by using SDH / OTN in Centralized Base Transceiver Station system using remote radio head (RRH) technology. The method includes: dividing the communication interface between the MU and the RRUs into a user plane and a control plane, the user plane mainly for carrying I / Q sampling data concerning the user data, and the control plane mainly for carrying the data concerning control signaling; forming the I / Q sampling data concerning the user data carried by the user plane into an I / Q data frame via an I / Q data frame adaptation layer, then forming the I / Q data frame into a GFP frame via GFP and transmitting it on SDH / OTN; and carrying the control signaling of the control plane on UDP / IP and / or TCP / IP, and further carrying IP packet on PPP and forming it into a frame by HDLC, transmitting the HDLC frame including the control plane signaling on the SDH / OTN via the control character channel of the GFP frame. According to the present invention, the existing SDH / OTN transmission network is utilized directly, which further reduces the management and maintenance operation needed for signal transmission, as well as networking cost.

A method and apparatus are provided that can combine the benefits of beamforming with transmit diversity. In one embodiment, the invention includes sampling a signal received from a remote radio at elements of an antenna array, deriving spatial parameters for transmitting a signal to the remote radio from an antenna array, sampling the signal received from the remote radio at elements of at least one additional antenna array, and deriving spatial parameters for transmitting a signal to the remote radio from the at least one additional antenna array. The invention further includes generating diversity parameters for transmitting a signal to the remote radio using each antenna array as an element of a diversity array, and transmitting a signal to the remote radio using the spatial parameters and the diversity parameters.

A modular wireless communications station includes a standard antenna interface, a wireless communications antenna, and a remote radio head. The standard interface includes an antenna mount for the wireless communications antenna and at least one radio head mount. The radio head mount includes at least one linear guided support structure. The wireless communications antenna includes a bracket configured to engage the antenna mount and at least one RF interconnection module, the wireless communications antenna being mounted on the antenna mount. The remote radio head(s) include a low friction car configured to engage the linear guided support structure of the standard interface and an RF connector configured to engage the RF interconnection module of the antenna. The remote radio head may slide into engagement with the antenna and locked into place.

Methods and apparatus to enable an extensible and scalable control channel for wireless networks. In one embodiment, an Enhanced Physical Downlink Control Channel (ePDCCH) is disclosed that is implemented with a flexible number of Physical Resource Blocks (PRBs). Advantages of the ePDCCH include, for example: more efficient spectral utilization, better frequency management across multiple serving entities (e.g., base stations and remote radio heads), and extensible payload capabilities that can scale to accommodate higher or lower control information payloads, as compared to prior art PDCCH solutions.

A central base station for interference management in a distributed antenna system comprises a processor; a memory; and a frequency partition module configured to divide the remote radio heads into clusters and allocate a frequency band to each cluster. Multiple clusters use the same frequency band and groups of clusters are formed. A joint scheduler is configured, for each group, to activate at most two clusters at any given time and deactivate remaining clusters in the group, one of the at most two activated clusters being a serving cluster of the group, and to associate one or more users with the serving cluster in the group. An interference alignment module is configured to apply downlink interference alignment between the at most two activated clusters in each group to align transmit directions of all interferences between the at most two activated clusters.

A mobile communication system of the present invention includes a plurality of remote radio heads configured to transmit a signal to user equipment and configure an antenna network and a centralized baseband pool configured to be connected to the antenna network. The centralized baseband pool performs clustering with respect to the plurality of remote radio heads so as to dynamically vary the number of the remote radio heads each included in a plurality of clusters.

A remote radio head unit (RRU) system for achieving high efficiency and high linearity in wideband communication systems is disclosed. The present invention is based on the method of adaptive digital predistortion to linearize a power amplifier inside the RRU. The power amplifier characteristics such as variation of linearity and asymmetric distortion of the amplifier output signal are monitored by a wideband feedback path and controlled by the adaptation algorithm in a digital module. Therefore, embodiments of the present invention can compensate for the nonlinearities as well as memory effects of the power amplifier systems and also improve performance, in terms of power added efficiency, adjacent channel leakage ratio and peak-to-average power ratio. The present disclosure enables a power amplifier system to be field reconfigurable and support multi-modulation schemes (modulation agnostic), multi-carriers, multi-frequency bands and multi-channels. As a result, the remote radio head system is particularly suitable for wireless transmission systems, such as base-stations, repeaters, and indoor signal coverage systems.

Various embodiments provide for systems, methods, or apparatuses that provide a fronthaul architecture that facilitates high fidelity and low latency communication between a radio processing unit, such as a baseband unit (BBU), which may be located a central office (CO), and a remote transceiver, which may comprise a remote radio head (RRH) or a remote radio unit (RRU), which may be located at remote cell site.

In one embodiment, a system for telecommunications includes a base band unit, a backhaul network, a shared network, a cascaded chain of remote radio heads, and an optical node coupled to the cascaded chain of remote radio heads. The backhaul network is coupled to the base band unit and to the shared network. The cascaded chain includes a first remote radio head coupled to a first set of antennas, a second remote radio head coupled to a second set of antennas. The second remote radio head is coupled to the first remote radio head through the shared network. The cascaded chain of remote radio heads is coupled to the shared network. The second remote radio head is configured to receive signals from the second set of antennas and communicate the signals to the first remote radio head. The first remote radio head is configured to receive signals from the first set of antennas, receive signals from the from the second remote radio head, and transmit the signals to the base band unit. The base band unit, the first remote radio head, and the second remote radio head communicate through a digital radio interface. The optical node is configured to communicate signals between the backhaul network and data subscribers accessing the shared network.

The invention relates to a method for transmitting a plurality of antenna signals in a wireless Base Transceiver Station (BTS) using Remote Radio Head (RRH) technology and the corresponding system. The method includes the steps of: transmitting signals over the transmit channel using Synchronous Digital Hierarchy (SDH) / Optical Transmission Network (OTN), multiplexing the plurality of antenna signals adopting the manners of time division multiplex or GFP frame-level multiplex; forming the multiplexed antenna signal stream and in-band control signaling stream into Generic Framing Procedure (GFP) frame; or forming the plurality of antenna signals and the plurality of respective control signals on the in-band control signaling channel into a plurality of respective GFP frames in parallel; and further mapping the GFP frames to STM-N / OTM-n frames, therefore multiplexing the plurality of antenna signals and the in-band control signaling stream to realize the SDH / OTN-based transmission. According to the invention, in the circumstance of using a plurality of antennas for transmitting signals, the strict time and phase relations between various antenna signals can be ensured, and also system complexity can be simplified, the transmission delays from various antenna signals to CBTS are totally the same.

The present invention relates to a method for a terminal to perform a handover in a cloud radio access network (C-RAN), including the steps of: receiving information on at least one candidate remote radio head (RRH); measuring the strength of received signals from at least one candidate RRH and a serving cell for the terminal; and, when the strength of the received signals from the candidate RRH and the serving cell of the terminal satisfy a predetermined relationship according to the measured result, transmitting feedback information, including the measured result, to the candidate RRH.

Embodiments of the present invention can be used to efficiently transmit access control and traffic information on separate spatial channels. In one embodiment, the invention includes assigning a conventional channel and a first training sequence to a first remote radio and a second training sequence to a second remote radio. Thereafter, the invention can include communicating with the first remote radio on a first spatial channel occupying the conventional channel using the first training sequence, and communicating with the second remote radio on a second spatial channel occupying the same conventional channel using the second training sequence.

A remote radio head is disclosed that comprises an interface for connecting the remote radio head to a base station via an asynchronous packet network, an absolute time reference source for (time-)synchronising a signal transceived by the remote radio head. A corresponding method for transmitting a transmit signal at a remote radio head comprises: receiving a data packet at an interface connecting the remote radio head to a base station via an asynchronous network, processing the data packet to form the transmit signal, determining an absolute time reference by means of an absolute time reference source local to the remote radio head, and transmitting the transmit signal in an absolute time-synchronised manner with respect to the absolute time reference. A method for receiving a receive signal at a remote radio head is also disclosed.

The present invention discloses a method for transmitting signal between a central channel processing Main Unit (MU) and one or more Remote Radio Units (RRUs) by using SDH / OTN in Centralized Base Transceiver Station system using remote radio head (RRH) technology. The method includes: dividing the communication interface between the MU and the RRUs into a user plane and a control plane, the user plane mainly for carrying I / Q sampling data concerning the user data, and the control plane mainly for carrying the data concerning control signaling; forming the I / Q sampling data concerning the user data carried by the user plane into an I / Q data frame via an I / Q data frame adaptation layer, then forming the I / Q data frame into a GFP frame via GFP and transmitting it on SDH / OTN; and carrying the control signaling of the control plane on UDP / IP and / or TCP / IP, and further carrying IP packet on PPP and forming it into a frame by HDLC, transmitting the HDLC frame including the control plane signaling on the SDH / OTN via the control character channel of the GFP frame. According to the present invention, the existing SDH / OTN transmission network is utilized directly, which further reduces the management and maintenance operation needed for signal transmission, as well as networking cost.

A system for routing signals in a Distributed Antenna System includes a plurality of Digital Multiplexer Units (DMUs). The plurality of DMUs are coupled and operable to route signals between the plurality of DMUs. Each of the plurality of DMUs is operable to receive a digital signal from a base band unit (BBU). The system also includes a plurality of Digital Remote Units (DRUs) coupled to at least one of the plurality of DMUs and operable to transport signals between DRUs and the at least one of the plurality of DMUs.

The invention belongs to the technical field of optical cables, and relates to an optical cable for a remote radio head. The optical cable comprises a central reinforcing part, a plurality of fillers, a plurality of tight-buffered optical fibers, peripheral reinforcing parts, a wrapping layer and a sheath layer. The optical cable is characterized in that the fillers and the tight-buffered optical fibers are distributed around the central reinforcing part at intervals and are parallel to the central reinforcing part, the peripheral reinforcing parts are positioned in cable core gaps formed by the central reinforcing part, the fillers and the tight-buffered optical fibers, the wrapping layer wraps the outside of the tight-buffered optical fibers, the sheath layer warps the outside of the wrapping layer in an extruded manner, and the diameter of each filler is larger than or equal to that of each tight-buffered optical fiber. The invention further discloses a manufacturing method of the optical cable. The optical cable mainly solves the problems that tight-buffered optical fibers are easily damaged by a cable twisting mode and are easily punctured by a wrapping layer and the like in the prior art. The optical cable has the main advantages of simple structure, easiness in manufacture, higher heat resistance and small additional attenuation change of the optical fibers used within a wide temperature range.

An apparatus and method for radio link monitoring in a wireless communication system are provided, in which a transmission point communicating with a network where a Base Station (BS) and at least one Remote Radio Head (RRH) coexist within a cell receives Reference Signal Configuration Information (RSCI) from the network to which the transmission point belongs, receives RSs of at least one RS type indicated by the received RSCI from the BS and the at least one RRH that coexist within the cell, and performs radio link monitoring using the received RSs of the at least one RS type.

The invention discloses a wireless communication networking method. The method includes the steps of distributing HPNs in an area providing service, arranging at least two fog remote radio heads (F-RRHs), conducting communication through a mode of directly having access to the HPNs when the movement speed of a user terminal is larger than a preset threshold value M1 or real-time voice service communication needs to be conducted, conducting communication through a local F-RRH mode when the movement speed of the user terminal is smaller than or equal to the preset threshold value M1 and the distance between the user terminal and a user terminal to be in communication with the user terminal is larger than a preset threshold value D1 and is smaller than or equal to a preset threshold value D2, and conducting communication through a global BBU pool mode when the movement speed of the user terminal is smaller than or equal to the preset threshold value M1 and the distance between the user terminal and the user terminal to be in communication with the user terminal exceeds the preset threshold value D2. By means of the method, the requirement for the capacity of fronthauls can be lowered, the signal processing pressure on a BBU pool in a cloud computing service can be lowered, and the transmission delay can be prolonged.

Disclosed is a method for a terminal deciding an uplink transmission power in a macro cell environment, comprising at least one remote radio head (RRH). The method for the terminal deciding the uplink transmission power, comprises the steps of: receiving from the base station configuration information on the base station and on a state channel information-reference signal (CSI-RS) of the at least one RRH and CSI-RS transmission power information; measuring the strength of a received signal of the CSI-RS which is received from the at least one RRH; and estimating downlink path loss that corresponds to a node that is set as a reception point or a reception RRH by using the configuration information on the CSI-RS and the CSI-RS transmission power information.

An improved digital radio head system and method for wireless communications is disclosed that simplifies the timing and synchronization between the access network, base station, and radio head. A satellite derived timing source is obtained at one or more of the remote radio heads where it is convenient to obtain and use the timing reference. The reference is transmitted back to the base station, if necessary, to synchronize the two. This is further synchronized at a lower accuracy through the access network.

A communication system improving the communication quality in a case where a plurality of communication devices having different sizes of ranges coexist, in which communication with a terminal device is possible, to thereby improve an entire throughput. In a case where a remote radio head (RRH) is installed in a coverage of a macro cell, an uplink resource transmitted from a user equipment (UE) to the macro cell, that is, an uplink carrier frequency band UL1 of the macro cell is received not only by the macro cell but also by the RRH. Then, the macro cell combines a reception signal regarding the uplink resource of the macro cell, which has been received by the macro cell, and a reception signal regarding the uplink resource of the macro cell, which has been received by the RRH.

A remote radio head unit (RRU) system for multiple operating frequency bands, multi-channels, driven by a single or more wide band power amplifiers. More specifically, the present invention enables multiple-bands RRU to use fewer power amplifiers in order to reduce size and cost of the multi-band RRU. The present invention is based on the method of using duplexers and / or interference cancellation system technique to increase the isolation between the transmitter signal and receiver signal of the RRU.

The invention relates to a method of signal transmission between a host BTS and Remote Radio Unit(s), and the BTS communication system thereof. The transmission channel between the host BTS and the Remote Radio Unit(s) uses wideband transmission links or a network, the method includes the following steps of: performing the transmission over the transmission channel using a Synchronous Digital Hierarchy (SDH) / Optical Transmission Network (OTN), forming a digital wireless signal data stream and an in-band control signaling stream transmitted over the transmission channel into a Generic Framing Procedure (GFP) frame which is further mapped to a STM-N / OTM-n frame, thereby multiplexing the digital wireless signal data stream and the in-band control signaling stream to realize SDH / OTN-based transmission. As a result, the wireless signal can be effectively transmitted between the RRH and the host BTS without specific transmission network, and the management and maintenance operation required by the signal transmission and the networking cost can be reduced.