Telecommunications system using directional antennas

• US 5,303,240 A
• Filed: 07/08/1991
• Issued: 04/12/1994
• Est. Priority Date: 07/08/1991
• Status: Expired due to Fees

• Current Assignee: Motorola, Inc. (Motorola Solutions, Inc.)
• Original Assignee: Motorola, Inc. (Motorola Solutions, Inc.)
• Inventors: D'Amico, Thomas V., Borras, Jaime A., Sharp, Ronald E.
• Primary Examiner(s): Olms, Douglas W.
• Assistant Examiner(s): Blum, Russell
• Application Number:
  US07/727,031
• Time in Patent Office: 1,009 Days
• Field of Search: 370/95.3, 379/60, 455/33.3, 455/33.4, 455/134, 455/135, 455/276.1, 455/277.1, 455/277.2, 342/368, 342/371, 342/372, 342/374, 342/377
• US Class Current: 370/347
• CPC Class Codes: H01Q 3/2605 Array of radiating elements provided with a feedback control over the element weights, e.g. adaptive arrays
• CPC Class Codes: H01Q 3/36 with variable phase-shifters
• CPC Class Codes: H04B 7/10 Polarisation diversity; Directional diversity

Abstract

A communication system 100 for determining the optimum direction (206) for transmitting and receiving a signal in a radio comprises a receiver for receiving a carrier signal being a time divided signal having an instruction signal, a transmitter for transmitting a time divided signal, a directional antenna (10) coupled to said receiver and transmitter, and a steering device (28) for changing the phase of the carrier signal in accordance with the instruction signal.

Claims

1. A device in a communication system capable of determining the optimum direction for receiving and transmitting a signal, comprising:

a receiver for receiving a carrier signal being a time divided signal;

at least one directional antenna being an array of phase delay antennas coupled to the receiver;

scanning means for sweeping the directional antenna in different directions within a TDMA time frame;

signal quality measuring means for determining an optimum antenna direction within the TDMA time frame;

steering means for selecting an optimum antenna direction; and

transmitting means coupled to said steering means for transmitting on said directional antenna according to said selected optimum antenna direction.

2. The device of claim 1, wherein said device comprises a pager.

3. The device of claim 1

wherein the steering means comprises the change in phase of the carrier signal in accordance with the received time divided signal having a training signal.

4. A device in a communication system capable of determining the optimum direction for receiving and transmitting a signal, comprising:

a receiver for receiving a carrier signal being a time divided signal;

at least one directional antenna coupled to the receiver;

scanning means comprising a microprocessor and an array of phase delay antennas for sweeping the directional antenna in different directions within a TDMA time frame;

signal quality measuring means for determining an optimum antenna direction within the TDMA time frame;

steering means for selecting an optimum antenna direction; and

transmitting means coupled to said steering means for transmitting on said directional antenna according to said selected optimum antenna direction.

5. A portable radio used in a communication system capable of determining the optimum direction for transmitting and receiving a signal, comprising:

a receiver for receiving a carrier signal being a time divided signal;

a transmitter for transmitting a time divided signal;

at least one directional antenna being an array of phase delay antennas coupled to the receiver and the transmitter;

scanning means for sweeping the directional antenna in different directions within a TDMA time frame;

signal quality measuring means for determining an optimum antenna direction within the TDMA time frame; and

steering means for selecting an optimum antenna direction.

6. The radio of claim 5

wherein the steering means comprises the change in phase of the carrier signal in accordance with the received time divided signal having a training signal.

7. A radio used in a communication system capable of determining the optimum direction for transmitting and receiving a signal, comprising:

a receiver for receiving a carrier signal being a time divided signal;

a transmitter for transmitting a time divided signal;

at least one directional antenna coupled to the receiver and the transmitter;

scanning means comprising a microprocessor and an array of phase delay antennas for sweeping the directional antenna in different directions within a TDMA time frame;

signal quality measuring means for determining an optimum antenna direction within the TDMA time frame; and

steering means for selecting an optimum antenna direction.

8. A communication system capable of determing the optimum direction for transmitting and receiving a signal in a radio, comprising:

a receiver for receiving a carrier signal being a time divided signal;

a transmitter for transmitting a time divided signal;

at least one directional antenna coupled to the receiver and the transmitter;

scanning means for sweeping the directional antenna in different directions within a TDMA time frame;

signal quality measuring means for determining an optimum antenna direction within the TDMA time frame; and

steering means for selecting an optimum antenna direction wherein the steering means comprises the change in phase of the carrier signal in accordance with the time divided signal having a training signal.

9. A communication system capable of determining the optimum direction for transmitting and receiving a signal in a radio, comprising:

a receiver for receiving a carrier signal being a time divided signal;

a transmitter for transmitting a time divided signal;

at least one directional antenna having an array of phase delay antennas coupled to the receiver and the transmitter;

scanning means for sweeping the directional antenna in different directions within a TDMA time frame;

signal quality measuring means for determining an optimum antenna direction within the TDMA time frame; and

steering means for selecting an optimum antenna direction.

10. The communication system of claim 9

wherein the steering means comprises a signal processor having a microcomputer and a digital-to-analog converter.

11. The communication system of claim 9

comprising a portion of an assigned TDMA time slot within a TDMA frame

12. A communication system capable of determining the optimum direction for transmitting and receiving a signal in a radio, comprising:

a receiver for receiving a carrier signal being a time divided signal;

a transmitter for transmitting a time divided signal;

at least one directional antenna coupled to the receiver and the transmitter;

scanning means for sweeping the directional antenna in different directions within a TDMA time frame;

signal quality measuring means for determining an optimum antenna direction within the TDMA time frame; and

steering means for selecting an optimum antenna direction wherein the steering means comprises a microprocessor and an array of phase delay antennas.

13. A communication system capable of determining the optimum direction for transmitting and receiving a signal in a radio, comprising:

a receiver for receiving a carrier signal being a time divided signal;

a transmitter for transmitting a time divided signal;

at least one directional antenna coupled to the receiver and the transmitter;

scanning means for sweeping the directional antenna in different directions within a TDMA time frame and wherein the scanning means comprises a microprocessor and an array of phase delay antennas;

signal quality measuring means for determining an optimum antenna direction within the TDMA time frame;

steering means for selecting an optimum antenna direction.

14. In a radio-frequency communications system, a method for improving telecommunications using a directional antenna, comprising the steps of:

at a first communication unit;

transmitting an information signal having a training signal;

at a second communication unit having an array of phase delay antennas with a plurality of antenna settings;

receiving said information signal by said array of antennas;

steering said array of antennas in a setting in accordance with said training signal within a TDMA time frame;

transmitting by said array of antennas in accordance with said training signal within the TDMA time frame;

wherein said training signal comprises a portion of a time slot within said TDMA time slot arrangement.

15. In a radio-frequency communications system, a method for improving telecommunications using a directional antenna, comprising the steps of:

at a first communication unit;

transmitting in an omni pattern an information signal having a training signal;

at a second communication unit having an array of phase delay antennas with a plurality of antenna settings;

receiving said information signal by said array of antennas;

steering said array of antennas in a setting in accordance with said training signal within a TDMA time frame; and

transmitting by said array of antennas in accordance with said training signal within the TDMA time frame;

wherein said omni pattern allows for the steering of said directional antenna and for a handoff controlled by said second communication unit.

16. In a communication system, a method of aiming an antenna primarily based on signal quality received during directional scanning, comprising the steps of:

at a base station;

(a) transmitting a TDMA information signal on a given frequency wherein said TDMA information signal includes a training signal comprising a portion of a time slot within a TDMA frame;

at a portable communication unit;

(a) receiving said TDMA information signal;

(b) scanning for the information signal having the best signal quality from all possible antenna directions within a TDMA time frame;

(c) measuring the signal quality of each information signal within the TDMA time frame; and

(d) assigning a given antenna direction based on the optimum signal quality received.

17. The method of claim 16, wherein said method of aiming an antenna comprises the further step of:

(e) continuing to measure for an optimum signal quality for each information signal and reassigning the antenna direction before the signal becomes corrupted.

18. The method of claim 16, wherein said method of aiming an antenna comprises the further step of:

(f) storing a history of antenna directions.

19. The method of claim 16, wherein said method of aiming an antenna comprises the further step of:

(g) controlling the handoff process by measuring the signal quality of other communication resources and determining when an inter-cell or intra-cell handoff is indicated.