Relay device and associated vehicle and method

• US 9,577,738 B2
• Filed: 01/30/2013
• Issued: 02/21/2017
• Est. Priority Date: 01/30/2013
• Status: Active Grant

• Current Assignee: Telefonaktiebolaget LM Ericsson
• Original Assignee: Telefonaktiebolaget LM Ericsson
• Inventors: Nilsson, Andreas, Asplund, Henrik, Coldrey, Mikael
• Primary Examiner(s): Trinh, Tan H
• Application Number:
  US14/764,329
• Publication Number:
  US 20150372747A1
• Time in Patent Office: 1,483 Days
• Field of Search: 455/25, 455/11.1, 455/16, 455/7, 455/9, 455/509, 455/418, 455/426.1, 455/67.11, 455/457, 455/437, 455/562.1, 455/18, 455/502, 455/500, 455/436, 375/211, 375/135, 375/137, 375/260, 375/329, 343/711, 370/315, 370/329, 370/331, 370/338, 370/310, 370/352, 370/308, 342/372
• US Class Current: 1/1
• CPC Class Codes: H01Q 1/246 specially adapted for base stations
• CPC Class Codes: H01Q 1/3216 where the road or rail vehicle is only used as transportation means
• CPC Class Codes: H01Q 25/00 Antennas or antenna systems providing at least two radiating patterns arrangements for changing or varying the orientation or the shape of the directional pattern H01Q3/00
• CPC Class Codes: H01Q 25/005 providing two patterns of opposite direction; back to back antennas H01Q25/004 takes precedence
• CPC Class Codes: H04B 7/1555 Selecting relay station antenna mode, e.g. selecting omnidirectional -, directional beams, selecting polarizations
• CPC Class Codes: H04B 7/2606 Arrangements for base station coverage control, e.g. by using relays in tunnels
• CPC Class Codes: H04W 88/02 Terminal devices
• CPC Class Codes: H04W 88/08 Access point devices

Abstract

It is presented a relay device arranged to act as a relay to provide relayed access for at least one wireless device within a vehicle to a cellular radio communication network. The relay device comprises: a relay node device comprising a vehicle antenna for communicating with the at least one wireless device; a first directional antenna directed in a first direction, the first directional antenna being connected to the relay node device; and a second antenna which is not directed in the first direction, the second antenna being connected to the relay node device. The first directional antenna and second antenna are arranged to communicate with fixed radio base stations of the cellular radio communication network; and the first direction is essentially parallel to a direction of travel of the vehicle. A corresponding vehicle and method are also presented.

Claims

1. A relay device arranged to be provided in a vehicle to act as a relay to provide relayed access for at least one wireless device within the vehicle to a cellular radio communication network, and configured to reduce a risk of handover failure when the vehicle moves from a first cell to a second cell, the relay device comprising:

a relay node device comprising a vehicle antenna for communicating with the at least one wireless device within the vehicle;

a first directional antenna directed in an essentially rearward direction to increase directional gain toward a first base station serving the first cell, the first directional antenna being connected to the relay node device;

a second directional antenna directed in an essentially forward direction to increase directional gain toward a second base station serving the second cell, the second directional antenna being connected to the relay node device; and

circuitry configured to combine signals of the first directional antenna and the second directional antenna,

wherein the increased directional gain toward the first and second base stations effectively increases an overlap of the first and second cells, thereby increasing handover time and reducing the risk of handover failure.

2. The relay device according to claim 1, wherein the relay node device consists of a single relay node.

3. The relay device according to claim 1, wherein the relay node device consists of two relay nodes.

4. The relay device according to claim 1, wherein for each one of the first directional antenna and the second directional antenna, a difference in directional gain at a constant elevation angle is configured to achieve a desired extension of handover time based on an expected operating condition.

5. The relay device according to claim 1, wherein for each one of the first directional antenna and the second directional antenna, a maximal difference in directional gain at a constant elevation angle is between 1.5 dB and 4.5 dB.

6. The relay device according to claim 1, wherein for each one of the first directional antenna and the second directional antenna, a maximal difference in directional gain at a constant elevation angle is about 3 dB.

7. The relay device according to claim 1, wherein the first directional antenna is arranged to be provided at a rear end of the vehicle and the second directional antenna is arranged to be provided at a front end of the vehicle.

8. The relay device according to claim 1, wherein the essentially forward direction deviates less than fifteen degrees from the opposite of the essentially rearward direction.

9. A vehicle comprising the relay device according to claim 1.

10. A method, performed in a relay device provided in a vehicle, the method comprising:

relaying communication between wireless devices in the vehicle and fixed radio base stations of a cellular radio communication network; and

reducing a risk of handover failure when the vehicle moves from a first cell to a second cell;

wherein the relay device includes;

a relay node device having a vehicle antenna for communicating with at least one of the wireless devices in the vehicle;

a first directional antenna directed in an essentially rearward direction to increase directional gain toward a first base station serving the first cell, the first directional antenna being connected to the relay node device;

a second directional antenna directed in an essentially forward direction to increase directional gain toward a second base station serving the second cell, the second directional antenna being connected to the relay node device; and

circuitry configured to combine signals of the first directional antenna and the second directional antenna,

wherein the increased directional gain toward the first and second base stations effectively increases an overlap of the first and second cells, thereby increasing handover time and reducing the risk of handover failure.