Dynamic coverage enhancement
A plurality of payload messages is communicated on a radio link of a cellular network between a terminal and an access node of the cellular network. Each one of the plurality of payload messages includes a data packet encoded according to a given redundancy version. The number of the plurality of payload messages may be dynamically and flexibly adjusted in some embodiments. Examples are given which may be applied for coverage enhancement in the Internet of Things or Machine Type Communication domain.
1. A node of a cellular network, comprising:
an interface configured to communicate with a terminal attached to the cellular network on a radio link, and
at least one processor configured to:
receive, from the terminal and via the interface, a first plurality of payload messages, each one of the first plurality of payload messages including a data packet encoded according to a given redundancy version,
decode the data packet based on the first plurality of payload messages,
selectively send, to the terminal and via the interface, at least one control message depending on said decoding, the at least one control message including a command prompting the terminal to send a second plurality of payload messages, each one of the second plurality of payload messages including the data packet encoded according to the given redundancy version,
receive, from the terminal and via the interface, the second plurality of payload messages, and
decode the data packet based on the first plurality of payload messages and the second plurality of payload messages.
2. The node of claim 1 ,
wherein the at least one processor is configured to execute said sending of the at least one control message if said decoding of the data packet based on the first plurality of payload messages fails.
3. The node of claim 1 ,
wherein the at least one processor is configured to selectively send the at least one control message depending on a bit error rate of the first plurality of payload messages.
4. The node of claim 3 ,
wherein the at least one processor is configured to execute said sending of the at least one control message if the bit error rate of the first plurality of payload messages is below a threshold.
5. The node of claim 1 ,
wherein the at least one processor is configured to access the interface to determine a quality of said communicating on the radio link,
wherein the at least one processor is configured to determine a number of the second plurality of payload messages depending on the quality of said communicating on the radio link.
6. The node of claim 1 ,
wherein the at least one processor is configured to selectively send, to the terminal and via the interface, at least one further control message depending on said decoding, the at least one further control message prompting the terminal to send a further plurality of payload messages, each one of the further plurality of payload messages including the data packet encoded according to a further redundancy version different from the given redundancy version.
7. The node of claim 1 ,
wherein the at least one processor is configured to negotiate, with the terminal and via the interface, a bundling policy indicating a default number of messages used for communication of data according to the same redundancy version,
wherein the first plurality of payload messages is communicated under the bundling policy,
wherein a number of the first plurality of payload messages equals the default number of payload messages.
8. The node of claim 7 ,
wherein the at least one processor is configured to re-negotiate, with the terminal and via the interface, the bundling policy depending on said decoding.
9. The node of claim 1 ,
wherein the at least one control message includes an indicator indicating the number of the second plurality of payload messages.
10. The node of claim 1 ,
wherein the at least one control message comprises a plurality of control messages, each one of the plurality of control messages including the command encoded according to a given redundancy version.
11. The node of claim 10 ,
wherein the number of the plurality of control messages equals the sum of the number of the first plurality of payload messages and the number of the second plurality of payload messages.
12. The node of claim 1 ,
wherein a bundled transmission set of payload messages communicated in subsequent transmission intervals of a channel implemented on the radio link comprises the first plurality of payload messages.
13. The node of claim 1 ,
wherein the at least one control message is a negative acknowledgement message of an Automatic Repeat Request protocol implemented by a Medium Access Layer of a communication protocol stack of the node, the negative acknowledgement message including an indicator negatively acknowledging receipt of the data packet.
14. A terminal, comprising:
an interface configured to communicate with a node of a cellular network on a radio link,
at least one processor configured to:
send, to the node and via the interface, a first plurality of payload messages, each one of the first plurality of payload messages including a data packet encoded according to a given redundancy version,
receive, from the node and via the interface, at least one control message, the at least one control message including a command prompting to send a second plurality of payload messages, each one of the second plurality of payload messages including the data packet encoded according to the given redundancy version,
send, via the interface and to the node, the second plurality of payload messages in response to receiving the at least one control message,
receive, from the node and via the interface, at least one further control message, the at least one further control message prompting the terminal to send a further plurality of payload messages, each one of the further plurality of payload messages including the data packet encoded according to a further redundancy version different from the given redundancy version, and
send, via the interface and to the node, the further plurality of payload messages in response to receiving the further control message.
15. A method, comprising:
receiving a first plurality of payload messages on a radio link, each one of the first plurality of payload messages including a data packet encoded according to a given redundancy version,
decoding the data packet based on the first plurality of payload messages,
depending on said decoding: selectively sending at least one control message on the radio link, the at least one control message including a command prompting to send a second plurality of payload messages, each one of the second plurality of payload messages including the data packet encoded according to the given redundancy version,
receiving the second plurality of payload messages, and
decoding the data packet based on the first plurality of payload messages and the second plurality of payload messages.
16. A method, comprising:
sending a first plurality of payload messages on a radio link, each one of the first plurality of payload messages including a data packet encoded according to a given redundancy version,
receiving at least one control message on a radio link, the at least one control message including a command prompting to send a second plurality of payload messages, each one of the second plurality of payload messages including the data packet encoded according to the given redundancy version,
in response to receiving the at least one control message: sending the second plurality of payload messages on a radio link,
receiving at least one further control message, the at least one further control message prompting to send a further plurality of payload messages, each one of the further plurality of payload messages including the data packet encoded according to a further redundancy version different from the given redundancy version, and
sending the further plurality of payload messages in response to receiving the further control message.