Phased array base station antenna system having distributed low power amplifiers

• US 6,337,659 B1
• Filed: 10/25/1999
• Issued: 01/08/2002
• Est. Priority Date: 10/25/1999
• Status: Expired due to Term

• Current Assignee: Gamma Nu, Inc.
• Original Assignee: Gamma Nu, Inc.
• Inventors: Kim, Sang-Gi
• Primary Examiner(s): PHAN, DAO LINDA
• Application Number:
  US09/426,198
• Time in Patent Office: 806 Days
• Field of Search: 342/194, 342/157, 342/354, 342/373, 342/374, 455/154.2, 455/341
• US Class Current: 342/373
• CPC Class Codes: H01Q 1/246 specially adapted for base stations
• CPC Class Codes: H01Q 25/008 lens fed multibeam arrays
• CPC Class Codes: H01Q 3/30 varying the relative phase between the radiating elements of an array H01Q3/2605, H01Q3/2658, H01Q3/2682, H01Q3/44 take precedence
• CPC Class Codes: H04B 7/0805 with single receiver and antenna switching H04B7/0822 takes precedence
• CPC Class Codes: H04B 7/10 Polarisation diversity; Directional diversity
• CPC Class Codes: Y02D 30/70 in wireless communication networks

Abstract

A phased array antenna system having low power amplifiers reduces power loss through several tens meters high frequency cables. The antenna system for transmitting a signal in a base station, comprising: a phased array unit for selecting an input signal through one of a plurality of beam ports, for dividing the input signal into a plurality of signals and for outputting the plurality of signals through a plurality of array ports, each of the signal having a linear phase difference according to difference of propagation path; a switch for receiving the input signal from a base station, for selecting one of the plurality of beam ports of said phased array and for transmitting the input signal to the selected beam port, responsive to a control signal transmitted from the base station; a plurality of low power amplifiers for low power amplifying the plurality of signals inputted from the plurality of array ports of said phased array; and phased array antennas for radiating the plurality of signals from said plurality of low power amplifiers, thereby providing a spatial power summation into a direction of equiphase plane allowing effective radiated power sufficiently enough to cover a cell into a steered direction selected by said switch.

Claims

1. A polarization diversity phased array base station antenna system, comprising:

a phased array means for selecting an input signal through one of a plurality of beam ports, for dividing the input signal into a plurality of signals and for outputting the plurality of signals through a plurality of array ports, each signal of the plurality of signals having a linear phase difference according to a difference of propagation path length;

a first switching means for receiving the input signal from a base station, for selecting one of the plurality of beam ports of said phased array means and for transmitting the input signal to the selected beam port, responsive to a control signal transmitted from the base station;

a plurality of amplifying means having a predetermined amplification factor for amplifying the plurality of signals inputted from the plurality of array ports of said phased array means;

first phased array antennas for radiating the plurality of signals from said plurality of amplifying means, providing a spatial power summation in an equiphase plane direction that enables an effective radiated power to cover a cell in a steered direction selected by said first switching means, and for receiving a signal radiated from a mobile station;

phased array duplexing means for transferring signals from said plurality of amplifying means to said first phased array antennas and for receiving and outputting received signals from said first phased array antennas;

second phased array means for receiving a plurality of signals from said phased array duplexing means through a plurality of array ports, each signal, of said plurality of signals, having a linear phase difference, and for allowing the plurality of signals to be in-phase and strengthened at a beam port;

second switching means for selecting a strengthened signal responsive to the control signal transmitted from the base station;

first low noise amplifying means for low noise amplifying a selected strengthened signal and transmitting the selected strengthened signal to the base station;

second phased array antennas for receiving a signal radiated from a mobile station;

third phased array means for receiving a plurality of signals from said second phased array antennas through a plurality of array ports, each signal having a linear phase difference, and for allowing the plurality of signals to be in-phase and strengthened at a beam port;

third switching means for selecting a strengthened signal in response to the control signal transmitted from the base station; and

second low noise amplifying means for low noise amplifying a selected strengthened signal and for transmitting the selected signal to the base station.

2. The antenna system of claim 1, wherein said antenna system is mounted on an antenna tower.

3. The antenna system of claim 1, wherein said phase array means comprises a microwave lens.

4. The antenna system of claim 1, wherein said phased array means comprises a Butler matrix.

5. The antenna system of claim 1, wherein said phased array means comprises a series of solid state phase shifters.

6. The antenna system of claim 1, wherein the control signal is transmitted from an interface card inside the base station, which is dialed up and commanded by a wireless modem from an operator located at a remote area.

7. A polarization diversity phased array base station antenna system, comprising:

a phased array device that selects an input signal through one of a plurality of beam ports, said phased array dividing the input signal into a plurality of signals, said plurality of signals being output through a plurality of array ports, each signal of said plurality of signals having a linear phase difference in accordance with a propagation path length difference;

a first switching device that receives said input signal from a base station, a beam port of said plurality of beam ports being selected by said first switching device in response to a control signal transmitted from the base station, so that the input signal is transmitted to said selected beam port;

a plurality of amplifiers that have a predetermined amplification factor to amplify said plurality of signals inputted from said plurality of array ports of said phased array device;

first phased array antennas that radiate said plurality of signals amplified by said plurality of amplifiers, providing a spatial power summation in an equiphase plane direction that enables an effective radiated power to cover a cell in a steered direction selected by said first switching device, and for receiving a signal radiated from a mobile station;

a phased array duplexing device that transfers signals from said plurality of amplifiers to said first phased array antennas and for receiving and outputting received signals from said first phased array antennas;

a second phased array device that receives a plurality of signals from said phased array duplexing device through a plurality of array ports, each signal, of said plurality of signals, having a linear phase difference, and for allowing the plurality of signals to be in-phase and strengthened at a beam port;

a second switching device that selects a strengthened signal responsive to the control signal transmitted from the base station;

a first low noise amplifier that low noise amplifies a selected strengthened signal, said selected strengthened signal being transmitted to the base station;

second phased array antennas that receive a signal radiated from a mobile station;

a third phased array device that receives a plurality of signals from said second phased array antennas through a plurality of associated array ports, each signal having a linear phase difference, and for allowing the plurality of signals to be in-phase and strengthened at a beam port;

a third switching device that selects a strengthened signal in response to the control signal transmitted from the base station; and

a second low noise amplifier that low noise amplifies a selected strengthened signal and for transmitting the selected signal to the base station.

8. The antenna system of claim 7, wherein said antenna system is mounted to a fixed structure.

9. The antenna system of claim 8, wherein said fixed structure comprises an antenna tower.

10. The antenna system of claim 7, wherein said phased array device comprises one of a microwave lens, a Butler matrix, and a phase shifter.