SUPPORTING DISTINCT SINGLE-INPUT SINGLE-OUTPUT (SISO) SERVICES IN A MULTIPLE-INPUT MULTIPLE-OUTPUT (MIMO) BASEBAND CIRCUIT, PARTICULARLY SUITED FOR A DISTRIBUTED ANTENNA SYSTEM (DAS)

摘要

One embodiment of the disclosure relates to supporting distinct single-input single-output (SISO) services in a multiple-input multiple-output (MIMO) baseband circuit, particularly suited for a distributed antenna system (DAS). In this regard, in one aspect, two communication paths in the MIMO baseband circuit are reconfigured to distribute two distinct SISO signals. A quadrature modulator modulates the two distinct SISO signals to two different radio frequency (RF) bands, respectively, based on a modulation frequency. In another aspect, the two or more distinct SISO signals are provided to the quadrature modulator using two intermediate frequencies (IFs) that are determined based on the center frequencies and bandwidths of the two different RF bands. By reconfiguring the MIMO baseband circuit to distribute the two distinct SISO signals, it is possible to retro-support new wireless communication services and/or new RF bands in existing DAS installations without replacing the MIMO baseband circuit.

主权项

1. A multiple-input multiple-output (MIMO) baseband circuit configured to support distinct single-input single-output (SISO) services, comprising:
a first MIMO path configured to distribute a first SISO signal; a second MIMO path configured to distribute a second SISO signal; a first quadrature modulator comprising a first SISO signal input coupled to the first MIMO path, the first SISO signal input configured to receive the first SISO signal; and a second quadrature modulator comprising a second SISO signal input coupled to the second MIMO path, the second SISO signal input configured to receive the second SISO signal; wherein:
the first quadrature modulator is configured to modulate the first SISO signal to a first radio frequency (RF) band based on a modulation frequency; andthe second quadrature modulator is configured to modulate the second SISO signal to a second RF band that is different from the first RF band based on the modulation frequency.