Cooperating arrangement for diversity stations

• US 4,287,598 A
• Filed: 12/17/1979
• Issued: 09/01/1981
• Est. Priority Date: 12/17/1979
• Status: Expired due to Term

• Current Assignee: Bell Telephone Laboratories, Inc. (Nokia Corporation)
• Original Assignee: Bell Telephone Laboratories, Inc. (Nokia Corporation)
• Inventors: Yeh, Yu S., Langseth, Rollin E.
• Primary Examiner(s): Bookbinder, Marc E.
• Application Number:
  US06/104,190
• Time in Patent Office: 624 Days
• Field of Search: 455/8, 455/10, 455/12, 455/15, 455/52, 340/147 SC
• US Class Current: 455/505
• CPC Class Codes: H04B 7/022 Site diversity; Macro-diversity using two or more spaced independent antennas H04B7/04
• CPC Class Codes: H04B 7/18534 for enhancing link reliablility, e.g. satellites diversity

Abstract

The present invention relates to a cooperating arrangement for a pair of space diversity stations (30 and 40) interconnected by a communication link (20) wherein each station normally communicates independently with a remote point (12) of the system while handling traffic related to a separate service region (32 and 42) or separate portion of an overall service region. At the occurrence of a fade condition at one of the two stations, the fading station alerts the other station of the pair of such condition, and both stations are enabled to cause the normal two-way communications between the faded station and the distant point to be routed over the communication link for two-way transmission between the non-faded station of the pair and the distant point along with the normal associated two-way transmissions between the non-faded station and the distant point.

Claims

1. A space diversity arrangement comprising:

a first transmitting and receiving cooperating diversity station (30) capable of both handling traffic associated with a first service region (32) via an associated distribution network (33) and providing two-way radio communication with a distant point (12) characterized in that

the arrangement further comprises;

a second transmitting and receiving cooperating diversity station (40) capable of both handling traffic associated with a second service region (42) via an associated distribution network (43) and providing two-way radio communication with the distant point (12);

a communication link (20) interconnecting the first and second stations;

fade detecting means (100) disposed at each of the first and second stations capable of detecting a fade condition occurring in transmissions between each of the first and second stations and the distant point for generating a control signal representative of such occurring fade condition; and

diversity switching means (70, 102, 104, 106, 108, 110, 116, 118₁ -118_N+1 and 120₁ -120_N+1) disposed at each of the first and second stations responsive to said control signal from the associated fade detecting means for causing the station detecting a fade condition to communicate with the distant point via the communication link and the station not detecting a fade condition, with the station not experiencing a fade condition thus providing two-way communication with the distant point for both the first and second station for as long as the fade condition exists while the first and second stations will handle the traffic associated with the first and second service region, respectively.

2. A space diversity arrangement in accordance with claim 1 characterized in that

the diversity switching means comprises:

means (104,

     106) at each of the first and second stations capable of generating a take-over signal to the other station via the communication link in response to a detected fade condition and detecting such take-over signal when received on the communication link from a fading station.

3. A space diversity arrangement in accordance with claim 2 characterized in that

the diversity switching means further comprises:

means (102,

     108) at each of the first and second stations capable of, in response to a detected fade condition at one of the stations, switching the two-way signal transmissions normally sent between the fading station and the distant point over the communication link to the non-faded station for two-way transmission between the non-faded station and the distant point along with the normal two-way transmissions between the non-faded stations and the distant point.

4. A space diversity arrangement in accordance with claim 2 or 3 characterized in that

the diversity switching means further comprises:

first buffering means (78, 80₁ -80_N+1, 116, 118₁ -118_N+1) at each of the first and second stations capable of both receiving and appropriately storing the normal signals from the associated service region for transmission to the distant point and, in response to a received take-over signal from the fading cooperating diversity station, receiving from the communication link from the fading station and appropriately storing the signals normally transmitted by the fading station to the distant point;

second buffering means (86, 88₁ -88_N+1, 120₁ -120_N+1) at each of the first and second stations capable of both receiving and appropriately storing the normal signals from the distant point destined for the associated service region and also in response to a received take-over signal from the fading cooperating diversity station, receiving and appropriately storing the signals from the distant point normally transmitted to the fading cooperating diversity station; and

transmitting means (70, 82, 90,

     110) coupled to the first and second buffering means capable of transmitting the signals stored in the first buffering means to the distant point and for transmitting the signals stored in the second buffering means destined for the associated service region and the fading cooperating diversity station to appropriate outputs of the service region and the communication link, respectively.

5. A transmitting and receiving cooperating diversity station (30 or 40) for use in a space diversity arrangement wherein a pair of such stations are spaced-apart and interconnected by a communication link (20) and wherein each station is capable of providing two-way communication with a distant point (12), the station comprising:

fade detecting means (100) capable of detecting a fade condition occurring in transmissions between the station and the distant point and for generating a control signal representative of such fade condition characterized in that

the station further comprises;

means (74₁ -74_n, 76, 94, 95₁ -95_n) capable of handling two-way traffic with an associated service region (32 or

     42) via an associated distribution network (33 or

     43); and

diversity switching means (70, 102, 104, 105, 108, 110, 116, 118₁ -118_N+1, 120₁ -120_N+1) capable of (a) being responsive to control signals from the fade detecting means for generating a take-over control signal which is applied to an input to the communication link for transmission to the other station of the pair of spaced-apart interconnected stations and for switching normal two-way communications with the distant point directly to the input to the communication link to permit such two-way communications to be transmitted via the communication link and the other station of the pair of spaced-apart interconnected stations to the distant point, and (b) being responsive to a take-over control signal received from the other station of the pair of spaced-apart interconnected stations at an output from the communication link for providing the capability of two-way communications between the transmitting and receiving cooperating diversity station and the distant point for both normal two-way communications associated with the related service region and two-way communications received on the communication link that would normally be sent by the other station of the pair of spaced-apart interconnected stations to the distant point.

6. A transmitting and receiving cooperating diversity station in accordance with claim 5 characterized in that

the diversity switching means comprises:

first buffering means (78, 80₁ -80_n+1, 116, 118₁ -118_N+1) capable of both receiving and appropriately storing the normal signals from the service region handling means for transmission to the distant point and, in response to a received take-over control signal from the other station of the pair of spaced-apart interconnected stations on the communication link, receiving from the communication link and appropriately storing signals normally transmitted by said other station of the pair of spaced-apart interconnected stations to the distant point;

second buffering means (86, 88₁ -88_N+1, 120₁ -120_N+1) capable of both receiving and appropriately storing the normal signals from the distant point destined for the associated service region and, in response to a take-over control signal received from the other station of the pair of spaced-apart interconnected stations on the communication link, receiving and appropriately storing the signals from the distant point normally transmitted directly to the other station connected to the communication link; and

transmitting means (70, 82, 90,

     110) coupled to the first and second buffering means capable of transmitting the signals stored in the first buffering means to the distant point at the appropriate time and for transmitting the signals stored in the second buffering means and destined for the associated service region and the other station of the pair of spaced-apart interconnected stations to the service region handling means and the communication link, respectively.

7. A method of providing a space diversity arrangement wherein a pair of space diversity stations (30 and 40) are interconnected by a communication link (20) and each station is capable of providing two-way radio communication with a distant point (12) of the system characterized in that

the method comprises the steps of:

(a) during a non-fade condition at each of the two space diversity stations, causing each of the stations to handle the traffic of a separate service region (32 or

     42) via an associated distribution network (33 or

     43) and for directly transmitting and receiving two-way communications with the distant point that are related to the associated service region; and

during a fade condition occurring at one of the two space diversity stations;

(b) detecting the occurrence of a fade condition at any one of the two stations;

(c) in response to step (b), transmitting a take-over control signal over the communication link from the fading station to the non-faded station of the pair of stations;

(d) enabling the fading station in response to step (b) for rerouting the normal direct two-way communications between the fading station and the distant point via the communication link to the non-faded station of the pair of stations while handling all the traffic of the associated service region; and

(e) concurrent with step (d) and in response to step (c), enabling the non-faded station of the pair for providing direct two-way communication between the non-faded station and the distant point for both signals to the service region associated with the non-faded station and signals associated with the faded station transmitted on the communication link.

8. A method of providing a space diversity arrangement in accordance with claim 7 characterized in that

in performing step (e), providing concurrent steps of:

(f) receiving and appropriately storing both the normal signals from the service region associated with the non-faded stations and the signals received on the communication link from the faded station;

(g) receiving and appropriately storing the signals from the distant point destined for both the service region associated with the non-faded station and the communication link for transmission to the faded station; and

(h) transmitting the signals stored in step (f) at the appropriate time and frequency band to the distant point and the signals stored in step (g) to the proper destinations of the associated service region and communication link.