Apparatus and methods for transmission of timing information
A method of operating a communications device in a wireless communications network is provided, the method comprising transmitting to an infrastructure equipment of the wireless communications network a time source indication, the time source indication indicating to the infrastructure equipment that the communications device is a source of timing information. The timing information may be in accordance with a non-3GPP protocol, may be generated outside of the wireless communications network, and/or may be used by entities (including logical protocol entities, applications and the like) which are outside of the scope of 3GPP specifications. An example of such timing information is time information which is compliant with the IEEE 802.1AS specification. According to the present methods, a wireless communications network can support time sensitive networking based on timing information which may have its origin and/or destination(s) outside the scope of the wireless communications network.
1 . A method of operating a communications device in a wireless communications network, the method comprising:
transmitting to an infrastructure equipment of the wireless communications network a time source indication, the time source indication indicating to the infrastructure equipment (i) that the communications device is acting as a timing information ingress entity by serving as a source of timing information and (ii) that the communications device is a point of ingress in the wireless communications network for the timing information; and
transmitting a request to the infrastructure equipment to apply a modified operational algorithm with respect to the communications device based on the time source indication, the modified operational algorithm including an operational algorithm that differs in some aspect from a corresponding algorithm applied with respect to a communications device which has not been determined to be a source of timing information.
2 . The method according to claim 1 , wherein
the communications device comprises a clock for generating the timing information, and
the method further comprises generating the timing information.
3 . The method according to claim 2 , further comprising
receiving an indication of an allocation of uplink communication resources from the infrastructure equipment, and
transmitting to the infrastructure equipment, using the allocated uplink communication resources, the timing information.
4 . The method according to claim 1 , further comprising receiving the timing information.
5 . The method according to claim 1 , wherein the transmitting to the infrastructure equipment of the wireless communications network the time source indication includes transmitting a radio resource control (RRC) setup complete message comprising the time source indication.
6 . The method according to claim 1 , wherein the transmitting to the infrastructure equipment of the wireless communications network the time source indication includes transmitting a radio resource control (RRC) reconfiguration complete message comprising the time source indication.
7 . The method of claim 1 , wherein the modified operational algorithm comprises a modified radio resource control (RRC) connection release algorithm or a modified radio resource control (RRC) connection suspend algorithm.
8 . The method of claim 1 , wherein the modified operational algorithm comprises allocating periodic communication resources to the communications device based on a periodicity of the timing information.
9 . The method of claim 1 , wherein the modified operational algorithm comprises a modified handover procedure where the infrastructure equipment initiates a handover of the communications device to a candidate cell in response to determining that a propagation delay of the candidate cell is lower than a propagation delay of a serving cell.
10 . The method of claim 1 , wherein the modified operational algorithm comprises the infrastructure equipment prioritizing downlink data transmissions to the communications device over downlink data transmissions to other communications devices.
11 . A method of operating an infrastructure equipment in a wireless communications network, the infrastructure equipment providing a wireless access interface for transmitting data to and receiving data from a communications device, the method comprising:
receiving a time source indication, the time source indication indicating to the infrastructure equipment (i) that the communications device is acting as a timing information ingress entity by serving as a source of timing information and (ii) that the communications device is a point of ingress in the wireless communications network for the timing information; and
applying a modified operational algorithm with respect to the communications device based on the time source indication indicating (i) that the communications device is acting as the timing information ingress entity by serving as the source of timing information and (ii) that the communications device is the point of ingress in the wireless communications network for the timing information, the modified operational algorithm including an operational algorithm that differs in some aspect from a corresponding algorithm applied with respect to a communications device which has not been determined to be a source of timing information.
12 . The method according to claim 11 , wherein the time source indication is received via the wireless access interface from the communications device.
13 . The method according to claim 11 , wherein the time source indication is received from a core network entity of the wireless communications network.
14 . The method according to claim 11 , further comprising:
in response to receiving the time source indication,
maintaining, in an active state, a radio resource control (RRC) connection with the communications device until either a request to release the RRC connection is received from the communications device or the infrastructure equipment determines that a serving cell of the communications device should be changed, and
allocating uplink communication resources for the transmission of the timing information by the communications device.
15 . The method according to claim 11 , wherein
the wireless access interface is provided in a first cell, and
the method further comprises:
determining that a serving cell of the communications device should be changed to a second cell based on a propagation delay in the first cell and a propagation delay in the second cell, and
in response to the determining that the serving cell of the communications device should be changed to the second cell and receiving the time source indication, initiating a handover of the communications device from the first cell to the second cell.
16 . The method according to claim 15 , wherein the determining that the serving cell of the communications device should be changed to the second cell includes determining that the propagation delay in the second cell is lower than the propagation delay in the first cell.
17 . An apparatus for operating in a wireless communications network, the apparatus comprising:
a transmitter configured to transmit signals via a wireless access interface provided by an infrastructure equipment of the wireless communications network,
a receiver configured to receive signals via the wireless access interface, and
circuitry configured to control the transmitter and the receiver so that the apparatus is operable:
to determine a propagation delay of a transmission of a signal transmitted via the wireless access interface,
to transmit a propagation delay indication to a timing information ingress entity that is a point of ingress in the wireless communications network for timing information or a timing information egress entity that is a point of egress in the wireless communications network for the timing information, the propagation delay indication being based on the determined propagation delay,
to receive the timing information received at the wireless communications network at the timing information ingress entity that is the point of ingress in the wireless communications network for the timing information,
to provide a time source indication, the time source indication indicating (i) that a communications device is acting as the timing information ingress entity by serving as a source of the timing information and (ii) that the communications device is the point of ingress in the wireless communications network for the timing information,
to apply or request the application of a modified operational algorithm with respect to the communications device based on the time source indication indicating (i) that the communications device is acting as the timing information ingress entity by serving as the source of the timing information and (ii) that the communications device is the point of ingress in the wireless communications network for the timing information, the modified operational algorithm including an operational algorithm that differs in some aspect from a corresponding algorithm applied with respect to a communications device which has not been determined to be a source of timing information, and
to transmit the timing information via the wireless access interface.
18 . The apparatus according to claim 17 , wherein
the apparatus is an infrastructure equipment of the wireless communications network, and
the apparatus provides the wireless access interface.
19 . The apparatus according to claim 17 , wherein the apparatus is a communications device.
20 . The apparatus according to claim 19 , wherein the apparatus is associated with the timing information ingress entity that is the point of ingress in the wireless communications network for the timing information or the timing information egress entity that is the point of egress in the wireless communications network for the timing information.