Point-to-multipoint digital radio frequency transport

A system for digital transport of a wireless spectrum, the system comprising:

• a first unit located at a first site, the first unit including at least one cable interface;
• a second unit remotely located from the first unit at a second site and communicatively coupled to the first unit by at least a first cable communicatively coupled to the at least one cable interface;
• a third unit remotely located from the first unit at a third site and communicatively coupled to the second unit;
• wherein the third unit is configured to receive, at the third site, a first analog wireless signal comprising first wireless spectrum and any transmissions from any wireless units within a first coverage area associated with the third unit;
• wherein the third unit is configured to generate first digital samples indicative of at least a first portion of the first wireless spectrum of the first analog wireless signal;
• wherein the third unit is configured to communicate the first digital samples to the second unit;
• wherein the second unit is configured to digitally sum the first digital samples with second digital samples indicative of at least a second portion of a second wireless spectrum of a second analog wireless signal to produce first summed digital samples;
• wherein the second unit is configured to communicate the first summed digital samples to the first unit using the first cable;
• and
• wherein the first unit is configured to derive an uplink analog radio frequency signal, in a form suitable for wireless transmission to a base station via an external interface of the base station, from the first summed digital samples, wherein the first unit is configured to output the uplink analog radio frequency signal to at least one receiver of the base station via the external interface of the base station.

A first unit used in digital transport of a wireless spectrum, the first unit comprising:

• a first cable interface configured to communicatively couple the first unit to a second upstream unit located remotely from the first unit at a second site through a first cable;
• a second cable interface configured to communicatively couple the first unit to a third downstream unit located remotely from the first unit at a third site, the second cable interface configured to receive first digital samples from the third downstream unit, the first digital samples indicative of at least a first portion of a first wireless spectrum of a first analog wireless signal comprising the first wireless spectrum and any transmission received at the third downstream unit positioned at the third site from any wireless units within a first coverage area associated with the third downstream unit;
• a digital summer configured to digitally sum the first digital samples with second digital samples indicative of at least a second portion of a second wireless spectrum of a second analog wireless signal to produce first summed digital samples;
• wherein the first cable interface is configured to communicate the first summed digital samples to the second upstream unit using the first cable, wherein the second upstream unit is configured to derive an uplink analog radio frequency signal from the first summed digital samples in a form suitable for wireless transmission to a base station via an external interface of the base station, wherein the second upstream unit is configured to output the uplink analog radio frequency signal to at least one receiver of the base station via the external interface of the base station.