Remote radio unit using adaptive compression in a distributed radio access network

A method, performed by a remote radio unit (RRU), for facilitating communication between a wireless terminal and a baseband unit (BBU) in a distributed radio access network (RAN), the method comprising:

• receiving a radio frequency signal from the wireless terminal;
• converting the radio frequency signal to digital baseband samples using receiver circuitry and an analog-to-digital converter;
• adaptively compressing the digital baseband samples, using adaptive compression circuitry, to create fronthaul uplink information;
• and
• sending the fronthaul uplink information over a fronthaul link to the BBU using an adaptive fronthaul protocol;
• wherein the method further comprises:
• monitoring the fronthaul link to capture fronthaul link information;
• determining a fronthaul link quality indicator based, at least in part, on the fronthaul link information that is captured;
• and
• sending the fronthaul link quality indicator to the BBU over the fronthaul link.

A method, performed by a remote radio unit (RRU), for facilitating communication between a baseband unit (BBU) and a wireless terminal in a distributed radio access network (RAN), the method comprising:

• receiving fronthaul downlink information over a fronthaul link from the BBU using an adaptive fronthaul protocol;
• generating frequency-domain samples, based on the fronthaul downlink information received;
• creating time-domain baseband samples from the frequency-domain samples;
• and
• converting the time-domain baseband samples into a radio frequency signal to send to the wireless terminal;
• wherein the method further comprises expanding frequency-domain data into the frequency-domain samples based on a tonemap descriptor and a set of modulation symbol descriptors;
• and
• wherein the fronthaul downlink information received comprises the tonemap descriptor describing a set of tones to be used to generate the radio frequency signal for transmission to the wireless terminal, the set of modulation symbol descriptors, and the frequency-domain data identifying a modulation symbol descriptor of the set of modulation symbol descriptors to be used for a tone of the set of tones for a particular time period.

A remote radio unit (RRU) to facilitate communication between a wireless terminal and a baseband unit (BBU) in a distributed radio access network (RAN), the RRU comprising:

• electronic circuitry to configured to couple to the BBU using a fronthaul link, wherein the electronic circuitry of the RRU is configured to:
• receive information from the BBU over the fronthaul link;
• identify a first set of reportable tones based on the information received from the BBU;
• receive a radio frequency signal from the wireless terminal;
• convert the radio frequency signal to digital baseband samples;
• adaptively compress the digital baseband samples to create fronthaul uplink information based on the information received from the BBU;
• and
• send the fronthaul uplink information over the fronthaul link to the BBU using an adaptive fronthaul protocol;
• and
• wherein the electronic circuitry of the RRU is further configured to adaptively compress the digital baseband samples to create the fronthaul uplink information by including, in the fronthaul uplink information, first frequency-domain information associated with a first period that is related only to the first set of reportable tones, wherein the first set of reportable tones is a subset of a set of received tones and at least one tone of the set of received tones is not included in the first set of reportable tones;
• and
• wherein the electronic circuitry of the RRU is further configured to adaptively compress the digital baseband samples to create the fronthaul uplink information by converting the digital baseband samples into the first frequency-domain information included in the fronthaul uplink information.

A remote radio unit (RRU) to facilitate communication between a wireless terminal and a baseband unit (BBU) in a distributed radio access network (RAN), the RRU comprising:

• electronic circuitry to configured to couple to the BBU using a fronthaul link, wherein the electronic circuitry of the RRU is configured to:
• wherein the electronic circuitry of the RRU is configured to:
• receive a radio frequency signal from a wireless terminal;
• convert the radio frequency signal to digital baseband samples;
• adaptively compress the digital baseband samples to create fronthaul uplink information;
• send the fronthaul uplink information over the fronthaul link to the BBU using an adaptive fronthaul protocol;
• monitor the fronthaul link to capture fronthaul link information;
• determine a fronthaul link quality indicator based, at least in part, on the fronthaul link information that is captured;
• and
• send the fronthaul link quality indicator to the BBU over the fronthaul link.

A remote radio unit (RRU) to facilitate communication between a wireless terminal and a baseband unit (BBU) in a distributed radio access network (RAN), the RRU comprising:

• electronic circuitry to configured to couple to the BBU using a fronthaul link, wherein the electronic circuitry of the RRU is configured to:
• receive fronthaul downlink information over the fronthaul link from the BBU using an adaptive fronthaul protocol;
• generate frequency-domain samples, based on the fronthaul downlink information received;
• create time-domain baseband samples from the frequency-domain samples;
• and
• convert the time-domain baseband samples into a radio frequency signal to send to the wireless terminal;
• wherein the electronic circuitry of the RRU is further configured to expand frequency-domain data into the frequency-domain samples based on a tonemap descriptor and a set of modulation symbol descriptors;
• and
• wherein the fronthaul downlink information received comprises the tonemap descriptor describing a set of tones to be used to generate the radio frequency signal for transmission to the wireless terminal, the set of modulation symbol descriptors, and the frequency-domain data identifying a modulation symbol descriptor of the set of modulation symbol descriptors to be used for a tone of the set of tones for a particular time period.