Low noise in-building distribution network for wireless signals

• US 6,560,441 B1
• Filed: 04/13/2000
• Issued: 05/06/2003
• Est. Priority Date: 04/15/1999
• Status: Expired due to Term

• Current Assignee: CommScope Technologies, LLC (CommScope Holding Company, Inc.)
• Original Assignee: Transcept, Inc. (Crown Castle International Corporation)
• Inventors: Sabat, John Jr., Oates, John H., Johnson, Thomas J.
• Primary Examiner(s): LE, THANH C
• Application Number:
  US09/548,878
• Time in Patent Office: 1,118 Days
• Field of Search: 455/422, 455/426, 455/450, 455/452, 455/14, 455/523, 455/517, 455/63, 370/335, 370/329
• US Class Current: 455/14
• CPC Class Codes: H04B 7/2606 Arrangements for base station coverage control, e.g. by using relays in tunnels

Abstract

A solution for providing an improved fading margin environment for in-building wireless coverage. An optical fiber or other available broadband signal distribution network is used to distribute signals between centrally located base transceiver station (BTS) equipment and remotely located transceiver equipment referred to herein as a cable microcell integrator (CMI). The CMIs are deployed in a configuration to provide radio frequency coverage in a desired microcell area such as a building floor. In a preferred embodiment, a leaky coaxial cable is used as a radiating element within the microcell.

Claims

1. A wireless communication system in which a plurality of cells are located substantially adjacent one another, the wireless communication system operating over a specified frequency range to provide signals in a forward direction from a central base transceiver station towards subscriber units located in the cells, the system comprising:

a hub interface converter, for accepting radio frequency signals from at least one base station, the radio frequency signals comprising at least one base station traffic signal modulated onto a radio frequency carrier (RF), for upconverting such radio frequency signals to a transport carrier signal, and for coupling such transport carrier signal as an forward transport signal onto an intercell transport medium;

a cable microcell integrator, coupled to the intercell transport medium for receiving the forward transport signal, the cable microcell integrator associated with a respective one of the cells, the cable microcell integrator further including a demodulator to translate the forward transport signal to corresponding transmit radio frequency signals; and

a distribution coaxial cable, coupled to the cable microcell integrator such that the transmit radio frequency signals are radiated in the respective cell as forward link signals using the coaxial cable itself as the energy radiating element;

the system additionally comprising;

a power divider, disposed between the cable microcell integrator and the distribution coaxial cable; and

a second distribution coaxial cable, connected to the power divider, such that the transmit radio frequency signals are radiated from both of the distribution coaxial cables.

2. A system as in claim 1 wherein the intercell transport medium is an optical fiber.

3. A system as in claim 1 wherein the intercell transport medium is a coaxial cable.

4. A system as in claim 1 wherein the cells are divided into sectors, and where cable integrators are deployed in two or more adjacent cell sectors.

5. A system as in claim 1 wherein Code Division Multiple Access (CDMA) is used to modulate the traffic signals onto the radio frequency carrier signals.

6. A system as in claim 1 wherein the cable microcell integrators additionally include modulators for accepting subscriber radio frequency signals as received over the distribution coaxial cable from the subscriber units in a reverse link direction, and for upconverting the subscriber radio frequency signals to a radio frequency carrier signal as a reverse link transport signal coupled to the intercell transport medium.

7. A system as in claim 6 wherein the hub interface converter additionally comprises a demodulator to translate the reverse transport signal to corresponding radio frequency signals within a reverse link bandwidth which are in turn coupled to one or more of the base stations.

8. A system in which a plurality of cells are located substantially adjacent one another, the wireless communication system operating over a specified frequency range to provide signals in a forward direction from a central base transceiver station towards subscriber units located in the cells, the system comprising:

a hub interface converter, for accepting radio frequency signals from at least one base station, the radio frequency signals comprising at least one base station traffic signal modulated onto a radio frequency carrier (RF), for upconverting such radio frequency signals to a transport carrier signal, and for coupling such transport carrier signal as an forward transport signal onto an intercell transport medium;

a cable microcell integrator, coupled to the intercell transport medium for receiving the forward transport signal, the cable microcell integrator associated with a respective one of the cells, the cable microcell integrator further including a demodulator to translate the forward transport signal to corresponding transmit radio frequency signals; and

a distribution coaxial cable, coupled to the cable microcell integrator such that the transmit radio frequency signals are radiated in the respective cell as forward link signals using the coaxial cable itself as the energy radiating element;

wherein the cable microcell integrators additionally include modulators for accepting subscriber radio frequency signals as received over the distribution coaxial cable from the subscriber units in a reverse link direction, and upconverting the subscriber radio frequency signals to a radio frequency carrier signal as a reverse link transport signal coupled to the intercell transport medium; and

the system additionally comprising;

a duplexer, disposed between the distribution coaxial cable and the cable microcell integrators such that both the forward link signals being transmitted to the subscriber units and the reverse link signals being received from the subscriber units travel over a common distribution coaxial cable.