Distributed telecommunications system

• US 5,761,619 A
• Filed: 03/23/1995
• Issued: 06/02/1998
• Est. Priority Date: 03/23/1995
• Status: Expired due to Term

• Current Assignee: Telefonaktiebolaget LM Ericsson
• Original Assignee: Telefonaktienbolaget L.M. Ericsson
• Inventors: Dahlin, Steinar, Danne, Anders
• Primary Examiner(s): Bost, Dwayne
• Assistant Examiner(s): MAUNG, NAY AUNG
• Application Number:
  US08/408,863
• Time in Patent Office: 1,167 Days
• Field of Search: 379/58, 379/59, 379/60, 455/33.1, 455/33.2, 455/33.3, 455/54.1, 455/54.2, 455/53.1, 455/188.1, 455/422, 455/428, 455/429, 455/432, 455/436-438, 455/442, 455/502, 455/507, 455/562, 370/328, 370/331, 370/336, 370/338
• US Class Current: 455/422.1
• CPC Class Codes: H04W 36/18 for allowing seamless reselection, e.g. soft reselection
• CPC Class Codes: H04W 88/08 Access point devices
• CPC Class Codes: H04W 88/085 Access point devices with remote components

Abstract

A cellular telecommunications system has a plurality of nodes, each for performing at least one of a number of cellular telecommunications system functions, including base station, speech coder, control processing, signal processing, local handoff, location register, and network interface functions. The nodes are interconnected by a network preferably comprising an optical fiber cable. In one aspect of the invention, the protocol that is used on the network is a high speed synchronous protocol, such as the DTM protocol. A first node in the system may be an antenna; an RF component coupled to the antenna; an analog-to-digital converter having an analog port and a digital port, the analog port being coupled to the RF component; and an optical fiber modem for connecting the digital port of the analog-to-digital converter to the network means. A second node in the system may be for performing base station controller functions, wherein the first and second nodes, together, operate as a distributed base station. In another aspect of the invention, some of the nodes may be transceivers, while other nodes include antennas coupled to frequency band filters. The network operates to permit any of the transceivers to be coupled to any one or more of the antennas, thereby permitting a handoff of a call from one antenna to another while maintaining use of the same transceiver, or permitting a handoff of a call from one transceiver to another while maintaining use of the same antenna.

Claims

1. A cellular telecommunications system comprising:

a plurality of nodes, each for performing at least one of a plurality of cellular telecommunications system functions;

network means for interconnecting the plurality of nodes,

wherein the network means operates in accordance with a high speed synchronous protocol

wherein the plurality of nodes includes;

a plurality of first nodes, each for performing transceiver functions on a frequency band filtered signal received from the network means; and

a plurality of second nodes, each comprising an antenna coupled to a first port of a frequency band filter, the frequency band filter having a second port for coupling to the network means, wherein the antenna supplies a received radio signal to the frequency band filter, and the frequency band filter converts the received radio signal into the frequency band filtered signal and supplies the frequency band filtered signal to the network means; and

wherein the network means operates as a switch for coupling any one of the first nodes to any one of the second nodes,

wherein the network means operates as a switch for coupling any one of the first nodes to any two or more of the second nodes, and

wherein;

an ongoing call utilizes a first communication path from a first one of the second nodes, through the network means, to a first one of the first nodes; and

the network means effects a handoff of the ongoing call by establishing a second communications path from the first one of the second nodes to a second one of the first nodes.

2. A cellular telecommunications system comprising:

a plurality of nodes, each for performing at least one of a plurality of cellular telecommunications system functions;

network means for interconnecting the plurality of nodes,

wherein the network means operates in accordance with a high speed synchronous protocol

wherein the plurality of nodes includes;

a plurality of first nodes, each for performing transceiver functions on a frequency band filtered signal received from the network means; and

a plurality of second nodes, each comprising an antenna coupled to a first port of a frequency band filter, the frequency band filter having a second port for coupling to the network means, wherein the antenna supplies a received radio signal to the frequency band filter, and the frequency band filter converts the received radio signal into the frequency band filtered signal and supplies the frequency band filtered signal to the network means; and

wherein the network means operates as a switch for coupling any one of the first nodes to anyone of the second nodes,

wherein the network means operates as a switch for coupling any one of the second nodes to any two or more of the first nodes.

3. A cellular telecommunications system comprising:

network means operating in accordance with a high speed synchronous protocol;

a plurality of antenna site means, coupled to the network means, each for performing bandwide and channel-wide filtering of a received radio signal, for converting the filtered radio signal into a digitized radio signal, and for supplying the digitized radio signal to the network means; and

a plurality of central site means, coupled to receive the digitized radio signal from the network means, each of the central site means performing demodulation and channel decoding on the digitized radio signal,

wherein each of the antenna site means utilizes the network means to send the same digitized radio signal simultaneously to any two of the plurality of central site means.

4. A cellular telecommunications system comprising:

network means operating in accordance with a high speed synchronous protocol;

a plurality of antenna site means, coupled to the network means, each for performing bandwide filtering of a received radio signal, for converting the filtered radio signal into a digitized radio signal, and for supplying the digitized radio signal to the network means; and

a plurality of central site means, coupled to receive the digitized radio signal from the network means, each of the central site means performing channel-wide filtering, demodulation and channel decoding on the digitized radio signal,

wherein each of the antenna site means utilizes the network means to send the same digitized radio signal simultaneously to any two of the plurality of central site means.

5. A cellular telecommunications system comprising:

network means operating in accordance with a high speed digital protocol;

a plurality of antenna site means, coupled to the network means, each for performing bandwide filtering of a received radio signal, for converting the filtered radio signal into a digitized radio signal, and for supplying the digitized radio signal to the network means; and

a plurality of central site means, coupled to receive the digitized radio signal from the network means, each of the central site means performing channel-wide filtering, demodulation and channel decoding on the digitized radio signal,

wherein the network means operates as a switch to handoff an ongoing call from a first central site means to a second central site means while continuing to use a same one of the antenna site means for the ongoing call.

6. The cellular telecommunications system of claim 5, wherein the high speed digital protocol is a DTM protocol.

7. The cellular telecommunications system of claim 5, wherein each of the antenna site means utilizes the network means to send the same digitized radio signal simultaneously to any two of the plurality of central site means.

8. A cellular telecommunications system comprising:

network means operating in accordance with a high speed digital protocol;

a plurality of antenna site means, coupled to the network means, each for performing channel-wide filtering of a received radio signal, for converting the filtered radio signal into a digitized radio signal, and for supplying the digitized radio signal to the network means; and

a plurality of central site means, coupled to receive the digitized radio signal from the network means, each of the central site means performing demodulation and channel decoding on the digitized radio signal,

wherein the network means operates as a switch to handoff an ongoing call from a first central site means to a second central site means while continuing to use a same antenna site means for the ongoing call.

9. The cellular telecommunications system of claim 8, wherein the high speed digital protocol is a DTM protocol.

10. The cellular telecommunications system of claim 8, wherein each of the antenna site means utilizes the network means to send the same digitized radio signal simultaneously to any two of the plurality of central site means.