Cellular base station augmentation

• US 7,236,807 B1
• Filed: 10/27/2000
• Issued: 06/26/2007
• Est. Priority Date: 10/28/1999
• Status: Expired due to Fees

• Current Assignee: Celletra Ltd. (Unity Wireless Corp.)
• Original Assignee: Celletra Ltd. (Unity Wireless Corp.)
• Inventors: Shapira, Joseph, Lemson, Paul
• Primary Examiner(s): Urban; Edward F.
• Assistant Examiner(s): Jackson; Blane J.
• Application Number:
  US09/697,770
• Time in Patent Office: 2,433 Days
• Field of Search: 455/562.1, 455/561, 455/115.3, 455/101, 455/272, 455/273, 455/334, 455/339, 455/341, 342/373, 342/375
• US Class Current: 455/562.1
• CPC Class Codes: H01Q 1/246 specially adapted for base stations
• CPC Class Codes: H01Q 21/08 the units being spaced along or adjacent to a rectilinear path waveguide fed H01Q21/0037
• CPC Class Codes: H01Q 21/24 Combinations of antenna units polarised in different directions for transmitting or receiving circularly and elliptically polarised waves or waves linearly polarised in any direction circularly polarised patch antennas H01Q9/0428; circularly polarised horns H01Q13/0241; cross-polarised horns H01Q13/0258; polarisation converters H01Q15/242; cross-polarised rear feeds H01Q19/136; crossed polarisation dual antenna H01Q25/001
• CPC Class Codes: H04B 7/0671 using different delays between antennas
• CPC Class Codes: H04B 7/0894 using different delays between antennas

Abstract

A system and method of augmenting existing and operational base stations to include multiple diversity schemes and to render passive antenna elements active is presented herein. The passive antenna array of the existing base station is replaced with an active antenna array, consisting of an active radiator unit that includes an array of both receive and transmit antenna elements. The transmit and receive antenna elements of the active radiator unit, respectively, are connected to transmit amplifiers and bandpass filters located at a masthead or at the top of the building.

Claims

1. A method for augmenting an existing base station, said existing base station including a main antenna array having transmit and receive elements and a diversity antenna array having receive elements, said existing base station thereby providing receive diversity, said method comprising:

replacing said diversity antenna array with a new diversity antenna array comprising both receive and transmit elements, said replacing being to augment said existing base station to provide both transmit and receive diversity; and

adding a time delay to a transmitter section of said new diversity antenna array to feed a time-delayed sample to said new diversity antenna array, said time-delayed sample being of a signal transmitted by said main antenna array.

2. A method for augmenting an existing base station, said existing base station including a main antenna array, which comprises both transmit and receive antenna elements, and a diversity antenna array, which comprises passive receive elements, said existing base station thereby providing receive diversity, said method comprising:

replacing said diversity antenna array with a new diversity antenna array comprising both receive and transmit elements, thereby to augment said base station to provide both transmit and receive diversity,

co-locating said receive and transmit elements at the top of a building to form one common array;

coupling a directional coupler to said main antenna array and to said new diversity antenna array, to sample a transmit signal emitted from said main antenna array; and

connecting an isolator to said main antenna array, in order to control spurious emissions emitted from said base station.

3. A method augmenting an existing base station augmentation according to claim 2, wherein said main antenna and said new diversity antenna are co-located.

4. A method of augmenting an existing base station augmentation according to claim 2, further including,

connecting a delay unit to a transmit port of said new diversity antenna array to feed a time-delays sample to said new diversity antenna array, said time-delayed sample being of a signal transmitted by said main antenna.

5. A method of augmenting an existing base station according to claim 2, wherein said isolator is a ferrite isolator.

6. A method of augmenting an existing base station according to claim 5, wherein said ferrite isolator possesses low internal intermodulation distortion.

7. An existing base station augmentation method according to claim 2, further including:

locating said directional coupling at the top of said building.