An apparatus (800,240) comprising means configured to: receive a wireless superposition signal, the wireless superposition signal comprising a plurality of wireless signals (221,222,223), received substantially simultaneously, that are individually transmitted from a respective plurality of devices (2011,2022,2033) substantially simultaneously and at the same frequency, wherein each of the wireless signals represents a set of parameter values (111,112,113,114) of a set of parameters (11 01, 1102, 1103, 1104); determine one or more sets of parameter values from the received wireless superposition signal by applying the wireless superposition signal to a model generated by a machine learning system, wherein the model is configured to: receive, as an input, a wireless superposition signal comprising an aggregation of a plurality of wireless signals each representative of a set of parameter values of a set of parameters, wherein each parameter value is configured to adopt one of two values, wherein each of the plurality of wireless signals comprises: a set of time slots respectively associated with the set of parameters, and an analogue representation of the set of parameter values wherein: one of the two values for a parameter is represented by a transmission of a pulse of a predetermined amplitude in a time slot associated with the parameter, and the other of the two values for a parameter is represented by an absence of a transmission of a pulse in a time slot associated with the parameter value: and output one or more sets of parameter values (211',212',213',214'). receive a wireless superposition signal, the wireless superposition signal comprising a plurality of wireless signals (221,222,223), received substantially simultaneously, that are individually transmitted from a respective plurality of devices (2011,2022,2033) substantially simultaneously and at the same frequency, wherein each of the wireless signals represents a set of parameter values (111,112,113,114) of a set of parameters (11 01, 1102, 1103, 1104); determine one or more sets of parameter values from the received wireless superposition signal by applying the wireless superposition signal to a model generated by a machine learning system, wherein the model is configured to: receive, as an input, a wireless superposition signal comprising an aggregation of a plurality of wireless signals each representative of a set of parameter values of a set of parameters, wherein each parameter value is configured to adopt one of two values, wherein each of the plurality of wireless signals comprises: a set of time slots respectively associated with the set of parameters, and an analogue representation of the set of parameter values wherein: one of the two values for a parameter is represented by a transmission of a pulse of a predetermined amplitude in a time slot associated with the parameter, and the other of the two values for a parameter is represented by an absence of a transmission of a pulse in a time slot associated with the parameter value: and output one or more sets of parameter values (211',212',213',214'). receive, as an input, a wireless superposition signal comprising an aggregation of a plurality of wireless signals each representative of a set of parameter values of a set of parameters, wherein each parameter value is configured to adopt one of two values, wherein each of the plurality of wireless signals comprises: a set of time slots respectively associated with the set of parameters, and an analogue representation of the set of parameter values wherein: one of the two values for a parameter is represented by a transmission of a pulse of a predetermined amplitude in a time slot associated with the parameter, and the other of the two values for a parameter is represented by an absence of a transmission of a pulse in a time slot associated with the parameter value: and a set of time slots respectively associated with the set of parameters, and an analogue representation of the set of parameter values wherein: one of the two values for a parameter is represented by a transmission of a pulse of a predetermined amplitude in a time slot associated with the parameter, and the other of the two values for a parameter is represented by an absence of a transmission of a pulse in a time slot associated with the parameter value: and one of the two values for a parameter is represented by a transmission of a pulse of a predetermined amplitude in a time slot associated with the parameter, and the other of the two values for a parameter is represented by an absence of a transmission of a pulse in a time slot associated with the parameter value: and output one or more sets of parameter values (211',212',213',214').