An apparatus for an access node of a wireless network, comprising: at least one processor; and at least one memory including computer program code, wherein the at least one memory and computer program code are configured, with the at least one processor, to cause the apparatus to perform the following: transmitting a message to a first terminal device connected to the access node, the message instructing the terminal device to carry out a random access procedure towards the access node; receiving a signal from the first terminal device during the random access procedure, the signal comprising a random access preamble; attempting, upon receiving the signal, detection of the random access preamble from the received signal and, upon detecting the preamble in the received signal, associating the received signal with information indicating that the received signal comprises the random access preamble; training, after said associating, a random access preamble detection process of the access node to detect the random access preamble by using the received signal comprising the random access preamble as a training input; and using the random access preamble detection process trained with the training input in detection of the random access preamble from a second terminal device not connected to the access node. at least one processor; and at least one memory including computer program code, wherein the at least one memory and computer program code are configured, with the at least one processor, to cause the apparatus to perform the following: transmitting a message to a first terminal device connected to the access node, the message instructing the terminal device to carry out a random access procedure towards the access node; receiving a signal from the first terminal device during the random access procedure, the signal comprising a random access preamble; attempting, upon receiving the signal, detection of the random access preamble from the received signal and, upon detecting the preamble in the received signal, associating the received signal with information indicating that the received signal comprises the random access preamble; training, after said associating, a random access preamble detection process of the access node to detect the random access preamble by using the received signal comprising the random access preamble as a training input; and using the random access preamble detection process trained with the training input in detection of the random access preamble from a second terminal device not connected to the access node. transmitting a message to a first terminal device connected to the access node, the message instructing the terminal device to carry out a random access procedure towards the access node; receiving a signal from the first terminal device during the random access procedure, the signal comprising a random access preamble; attempting, upon receiving the signal, detection of the random access preamble from the received signal and, upon detecting the preamble in the received signal, associating the received signal with information indicating that the received signal comprises the random access preamble; training, after said associating, a random access preamble detection process of the access node to detect the random access preamble by using the received signal comprising the random access preamble as a training input; and using the random access preamble detection process trained with the training input in detection of the random access preamble from a second terminal device not connected to the access node.