The phrase "acknowledgement sent" is correct and usable in written English.
It can be used to indicate that a message or notification has been received and confirmed, often in a professional or formal context.
Example: "Thank you for your email. Acknowledgement sent regarding your request for information."
Alternatives: "Confirmation sent" or "Receipt acknowledged."
Fig. 5 Example of collision between an uplink packet and an acknowledgement sent by the base station.
Thus, if an acknowledgement sent by a user is not received by other users, the uninformed users keep obsolete packets.
Please note that when a packet is sent by an end-device, it can collide either with an acknowledgement sent by the base station or with an uplink packet sent by another end-device.
However, when node A is slightly ahead of node D, the acknowledgement sent by node B in response to A's message will collide with the message from D to C. In simulation, the clocks of different nodes run exactly at the same rate.
Hence, if users do not receive acknowledgements sent by others, there is no degradation in performance, only a requirement for slightly longer buffers.
Furthermore, it is also important to note that the assumption that acknowledgements sent by the receivers are received correctly by other receiving stations is not mandatory and was made only for the sake of simplicity.
As a consequence, an uplink packet can collide with a downlink packet (acknowledgement) only if the acknowledgement is sent before the packet.
sd Successful downlink: the end-device receives the acknowledgement sa Successful acknowledgement: the downlink transmission is successful, the acknowledgement is sent and does not collide with another packet.
This acknowledgement is sent after a time interval denoted T d.
After the data packet is received by the destination node, no acknowledgement is sent back.
As illustrated in Fig. 3, this acknowledgement is sent, by the base station, after a fixed receive delay denoted T d.
