Relaying protocol in a cellular telecommunications network

Abstract

An application method implemented by a device desiring to be an applicant for relaying data between an object and a base station in a cellular network, the object and the device being synchronized and connected to the base station. The device emits a request, over a random-access channel, to request resources of the network to relay the data, the request including an identifier of the object. If the base station selects a device from among the applicant devices, it allocates resources in the network for this device and sends a positive response to the selected device.

Claims

1. An application method implemented by a device desiring to be an applicant for relaying data between an object and a base station in a cellular network, the object and said device being synchronized and connected to the base station, this method including: emitting a request, over a random-access channel, to request resources of said network to relay said data, said request corresponding to an application to relay the data and including an identifier of said object; receiving a response to said request coming from said base station; and the device relaying the data or not relaying the data as a function of said response.

2. The application method as claimed in claim 1 wherein said random-access channel is the PRACH (Physical Random-Access Channel).

3. The application method as claimed in claim 1 wherein said request includes a request for resources from said network to transmit to the device data of its own.

4. The application method as claimed in claim 1 wherein said identifier is a temporary or permanent identifier.

5. The application method as claimed in claim 1 wherein said identifier is encoded into said request by a combination of a time slot and a frequency.

6. A selection method implemented by a base station to select an applicant device for relaying data between an object and said base station in a cellular network, the object and said device being synchronized and connected to said base station, this method including: receiving, from at least one device, a request emitted by this device, over a random-access channel, to request resources of said network to relay said data, said request including an identifier of said object; selecting a single device from among said at least one devices; allocating resources in said network and sending a positive response to the selected device; and sending a negative response to any non-selected device of the at least one device for relaying the data.

7. The selection method as claimed in claim 6 wherein said positive response further includes said identifier of the object.

8. The selection method as claimed in claim 6 wherein said request further includes a request for resources for said device's own data, and the method includes sending a response as to the allocation of the resources for the device's own data.

9. A device desiring to be an applicant for relaying data between an object and a base station in a cellular network, the object and said device being synchronized and connected to the base station, this device including: a processor; and a non-transitory computer readable medium comprising instructions stored thereon which when executed by the processor configure the device to: emit a request, over a random-access channel, to request resources of said network to relay these data, this request including an identifier of said object; receive a response to said request coming from said base station; relay the data or not relaying the data as a function of said response.

10. A base station configured to select an applicant device for relaying data between an object and said base station in a cellular network, the object and said device being synchronized and connected to said base station, the base station including: a processor; and a non-transitory computer readable medium comprising instructions stored thereon which when executed by the processor configure the base station to: receive, from at least one device, a request emitted by this device, over a random-access channel, to request resources of said network to relay said data, said request including an identifier of said object; select a single device from among said at least one device; allocate said resources in said network and send a positive response to said selected device; and sending a negative response to any non-selected applicant device among the at least one device for relaying the data.

11. A non-transitory computer readable medium having stored thereon instructions which, when executed by a processor, cause the processor to implement the application method of claim 1.

12. A non-transitory computer readable medium having stored thereon instructions which, when executed by a processor, cause the processor to implement the selection method of claim 6.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0047] Other features and advantages of this invention will become apparent from the description given below, with reference to the appended drawings which illustrate an exemplary embodiment thereof devoid of any limitation. In the figures:

[0048] FIG. 1 already described illustrates a relaying mechanism of the prior art;

[0049] FIG. 2 shows a device and a base station in accordance with a particular embodiment of the invention in their environment;

[0050] FIG. 3 illustrates a random-access mechanism in accordance with the prior art;

[0051] FIG. 4 shows an application method and a selecting method in accordance with a particular embodiment of the invention;

[0052] FIG. 5 shows an application method and a selecting method in accordance with another particular embodiment of the invention;

[0053] FIG. 6A shows the functional architecture of a device in accordance with a particular embodiment of the invention;

[0054] FIG. 6B shows the functional architecture of a base station in accordance with a particular embodiment of the invention;

[0055] FIG. 7A shows the hardware architecture of a device in accordance with a particular embodiment of the invention; and

[0056] FIG. 7B shows the hardware architecture of a base station in accordance with a particular embodiment of the invention.

DESCRIPTION OF THE EMBODIMENTS

[0057] FIG. 2 shows a connected object MTD, two devices UE1, UE2 and a base station gNB in a cellular network NET, the devices UE1, UE2 and the base station gNB being in accordance with embodiments of the invention. The invention is described thus in the example of 5G. It is applicable in the same way in a 4G network, the base stations being of eNB type.

[0058] It is assumed that the devices UE1, UE2 and the connected object MTD are synchronized and connected to the base station gNB.

[0059] There will now be a reminder, with reference to FIG. 3, of the random-access mechanism implemented in accordance with the prior art, in such a network.

[0060] In a known manner in such a network, when a terminal T (generic name chosen to denote the device UE1, UE2 or the connected object MTD) wishes to transmit data over the network, it emits a request on a random-access PRACH channel to request resources from the network. These resources are managed by the base station gNB.

[0061] More precisely, and as described in the document TS 36.211, the terminal randomly chooses a preamble from among a set of available preambles reserved for a contention process and it transmits its request (step B1) in a short message in the first available time slot of the random access. The sending of this short message is done cyclically.

[0062] These requests are listened to and received by the base station gNB which decides whether or not to allocate the requested resources. It responds (step B2) to this PRACH request by a RAR (Random Access Response) message, this message indicating whether the requested resources have been allocated or refused.

[0063] In a manner known by those skilled in the art, this response message also includes a time alignment TA which allows the terminal to synchronize. The terminal adjusts its transmission time to the TA received and transmits (step B3) a Radio Resource Control (RRC) message through the PUSCH (Physical Uplink Shared Channel) up channel. If the base station gNB correctly decodes the message sent in step B3, it transmits (step B4) the contention resolution to the terminal T. If the terminal T has not correctly received the RAR response or the contention resolution within a set time window, it starts the random access procedure again in step B1.

[0064] FIG. 4 illustrates an application method and a selection method in accordance with a first particular embodiment of the invention.

[0065] It is assumed that the devices UE1, UE2 and the connected object MTD are connected and synchronized with the base station gNB.

[0066] It is assumed in this example that the devices UE1 and UE2 have received a RR (Request for Relay) broadcast by the connected object, to relay a message from this object intended for the base station.

[0067] It is assumed in this example that the device UE1 and the device UE2 each wish to be an applicant for relaying a message of the connected object MTD.

[0068] In the exemplary embodiment described here, if the connected object broadcasts the message to be relayed at the same time as the relay request, each of the devices UE1 and UE2 stores this message in its memory while waiting to find out whether or not its application has been chosen by the base station.

[0069] In accordance with the invention, during a step E10, each of the devices UE1, UE2 emits a request over the random-access PRACH channel to request resources from the network to relay this message. This request includes an identifier ID_MTD of the connected object, for example its IMEI, TMSI or RA-RNTI identifier.

[0070] These requests are received by the base station gNB during a step F10.

[0071] During a step F20, the base station gNB selects a single device to relay the message of the connected object MTD.

[0072] In the exemplary embodiment described here, it selects the first applicant, namely the device UE1.

[0073] During a step E30 known to those skilled in the art, the base station gNB allocates resources in the network to allow the device UE1 to relay the message of the connected object.

[0074] During a step E40, it sends a positive RAR (Random Access Response) including the resources allocated to the device UE1 and a negative response to the device UE2. This RAR is identical to the RAR of the prior art previously described with reference to the step B2 of FIG. 3.

[0075] Consequently, in this first embodiment, only the step B1 is modified. The modification consists in modifying the PRACH preamble to contain an identifier of the relayed connected object MTD.

[0076] The devices UE1, UE2 receive this response during a step F20. The device UE1 understands that it has been chosen to relay the message of the connected object MTD and the device UE2 understands that its request has been rejected.

[0077] The random-access mechanism continues as previously described with reference to the steps B3 and B4 of FIG. 3.

[0078] FIG. 5 illustrates an application method and a selection method in accordance with a second particular embodiment of the invention.

[0079] In this embodiment, it is assumed that the device UE1 wishes to be an applicant for relaying a message of the connected object MTD and that this device UE1 also wishes to request resources for its own data.

[0080] In this embodiment of the invention, the device UE1 emits a single request over the random-access PRACH channel to request (i) resources from the network to relay the message of the connected object and (ii) resources to transmit its own data. In accordance with the invention this request includes an identifier ID_MTD of the connected object, for examples its IMEI, TMSI or RA-RNTI identifier.

[0081] This request is received by the base station gNB during a step F10.

[0082] During a step F20, the base station gNB decides whether or not to select the device UE1 to relay the message of the connected object MTD. If such is the case, the base station gNB allocates (step F30) resources in the network to allow the device UE1 to relay the message of the connected object.

[0083] During this same F20, the base station gNB decides whether or not to allocate resources to the device UE1 for its own needs. If such is the case, the base station gNB allocates (step F30) resources to the device UE1 for its own data.

[0084] In this embodiment of the invention, the base station responds (F40) to the device UE1 on the two allocation requests. This response can be done in a single RAR message or as shown in FIG. 5 in two RAR messages.

[0085] In the embodiment described here, the RAR to the request for allocation of resources to relay the data of the connected object MTD includes the identifier ID_MTD of this object.

[0086] FIG. 6A functionally represents a device UE desiring to be an applicant for relaying data between an object and a base station in a cellular network, this device being in accordance with a particular embodiment of the invention. It includes:

a module ME10 configured to emit a request, over a random-access channel, to request resources of a network to relay data between an object and a base station, this request including an identifier of this object;
a module ME20 for receiving a response to this request coming from the base station;
the application of the device being chosen or rejected as a function of said response.

[0087] FIG. 6B functionally represents a base station gNB configured to select an applicant device to relay data between an object and this base station in a cellular network, the object and the device being synchronized and connected to this base station. It includes:

a module MF10 for receiving, coming from at least one device, of a request transmitted by this device, over a random-access channel), to request resources of said network to relay said data, this request including an identifier of the object;
a module MF20 for selecting a single device (UE1) from among said applicant devices;
a module MF30 for allocating said resources in said network and sending a positive response to said selected device; and
a module MF40 for sending a negative response to said unselected applicant devices.

[0088] FIG. 7A shows the hardware architecture of a device UE in accordance with the invention. In the embodiment described here, this device UE has the hardware architecture of a computer. It particularly comprises a processor 20, a random-access memory 21, a read-only memory 22, a non-volatile flash memory 23 and communication means 24. Such means are known per se and are not described in further detail here.

[0089] The read-only memory 22 constitutes a recording medium in accordance with the invention, readable by the processor 20 and on which is here recorded a computer program ProgUE in accordance with the invention, this program particularly including instructions making it possible, when they are executed by the processor 20, to: [0090] detect a request for relay; [0091] emit a request, over a random-access channel to request resources of a network to relay data between an object and a base station, this request including an identifier of this object; [0092] receive a response to this request coming from the base station; [0093] understand that the application of the device has been chosen or rejected as a function of this response; [0094] implementing the steps B3 and B4 of the random access procedure described with reference to FIG. 3.

[0095] FIG. 7B shows the hardware architecture of a base station gNB in accordance with the invention. In the embodiment described here, this base station gNB has the hardware architecture of a computer. It particularly comprises a processor 10, a random-access memory 11, a read-only memory 12, a non-volatile flash memory 13 and communication means 14. Such means are known per se and are not described in further detail here.

[0096] The read-only memory 12 constitutes a recording medium in accordance with the invention, readable by the processor 10 and on which is here recorded a computer program ProgNB in accordance with the invention, this program particularly including instructions making it possible, when they are executed by the processor 20, to: [0097] receive, coming from at least one device, a request emitted by this device, over a random-access channel, to request resources of said network to relay said data, this request including an identifier of the object; [0098] select a single device (UE1) from among said applicant devices; [0099] allocate resources in said network and send a positive response to the selected device; [0100] send a negative response to the applicant devices not selected; [0101] implement steps B3 and B4 of the random access procedure described with reference to FIG. 3.