TECHNICAL FIELD

The disclosure relates generally to telecommunications and, more particularly (although not necessarily exclusively), to a digital multichannel interface between a base station and a repeater unit.

BACKGROUND

A DAS can be used to extend wireless coverage in an area through the use of one or more repeaters and multiple remote units coupled to each repeater. Repeaters can be coupled to one or more base stations that can each manage wireless communications for different cell sites. A repeater can receive downlink signals from the base station and distribute downlink signals in analog or digital form to one or more remote units. The remote units can transmit the downlink signals to user equipment devices within coverage areas serviced by the remote units. In the uplink direction, signals from user equipment devices may be received by the remote units. The remote units can transmit the uplink signals received from user equipment devices to the repeater. The repeater can transmit uplink signals to the serving base stations.

A base station can include a digital baseband unit and a radio transceiver unit that communicate using a digital optical interface. Industry communication standards, such as the Open Base Station Architecture Initiative (“OBSAI”) or Common Public Radio Interface (“CPRI”) standards, can be used to implement the digital optical interface between the digital baseband unit and radio transceiver unit. For example, the baseband unit of a base station can include several CPRI output ports. Each port can be input into various radio transceiver units.

The radio transceiver units of the base station can interface with a repeater using a radio frequency communication link. To communicate with the repeater, each radio transceiver unit in the base station can include hardware for signal processing and digital-to-analog conversion of incoming single carrier I/Q and control data streams to RF signals output at antenna ports. The use of a radio frequency communication link between the base station and the repeater can lead to higher equipment costs and increased power consumption due to the signal processing for digital-to-analog conversion and high powered RF amplification.

SUMMARY

In one aspect, a digital multichannel interface for a base station is provided. The digital multichannel interface for the base station can include a base station downlink interface. The base station downlink interface can receive multiple raw downlink I/Q data streams from a digital baseband unit via a digital front end and receive frame timing information. The frame timing information can be extracted from uplink transmit frames received from a repeater unit by a base station uplink interface in the base station. The base station downlink interface can also generate downlink transmit frames including a plurality of reformatted wideband downlink I/Q data streams according to the frame timing information and provide the downlink transmit frames to the repeater unit.

In another aspect, a digital multichannel interface for a repeater unit is provided. The digital multichannel interface for the repeater unit can include a repeater uplink interface that can receive frame timing information extracted from downlink transmit frames received from a base station by a repeater downlink interface in the repeater. The repeater uplink interface can also generate uplink transmit frames including a plurality of reformatted wideband uplink I/Q data streams according to the frame timing information and provide the uplink transmit frames to a base station uplink interface.

In another aspect, a method is provided. The method can involve a base station downlink interface receiving multiple raw wideband downlink I/Q data streams. The method can also involve the base station downlink interface receiving a base station framing clock signal that includes frame timing information generated at a repeater unit. The method can further involve generating downlink transmit frames by multiplexing the reformatted wideband downlink I/Q data streams according to the frame timing information included in the base station framing clock signal. The method can also involve transmitting the downlink transmit frames to the repeater unit.

In another aspect, a digital multichannel interface for a base station is provided. The digital multichannel interface can include a base station downlink interface configured to receive multiple raw wideband downlink I/Q data streams from a digital front end. The digital front end interfaces with a baseband unit of the base station. The digital multichannel interface can also generate serialized reformatted wideband downlink I/Q data streams by sampling the plurality of wideband downlink I/Q data streams and multiplexing the sampled plurality of wideband downlink I/Q data streams. The digital multichannel interface can further provide the serialized reformatted wideband downlink I/Q data streams to a repeater downlink interface of a repeater unit. The repeater unit can be configured to transmit information carried by the serialized reformatted wideband downlink I/Q data streams to one or more remote units configured to provide the downlink I/Q data streams to user equipment devices.

