Abstract: A method for detecting particle filter cleanliness includes receiving calibration data for a particle filter. The calibration data represents an acoustic spectrum. The method further includes receiving operational acoustic data from a sensor located in a system comprising a fan and the particle filter, deriving a second acoustic spectrum from the operational acoustic data, comparing at least part of the acoustic spectrum with a corresponding part of the second acoustic spectrum, determining a frequency shift between the acoustic spectrum and the second acoustic spectrum based on the comparing step, and providing an output based on the frequency shift.

Abstract: A user of a combined mobile telephone and IPDC receiver (10) accesses a WAP portal (16) through the Internet (82) and/or a mobile telephone network (81). The WAP portal (16) provides a service menu, comprising a number of links to service menus further down in the hierarchy or to IPDC services. The WAP portal (16) is provided with information relating to IPDC services by an IPDC operator (80). This information includes at least the name of the service, the IP address and the port number relating to each service. The information may additionally include a Network Information Table, IP/MAC Notification Table and Program Mapping Table, although this information may be provided to the mobile terminal instead by broadcast from a DVB transmitter (13).

Abstract: A user of a combined mobile telephone and IPDC receiver (10) accesses a WAP portal (16) through the Internet (82) and/or a mobile telephone network (81). The WAP portal (16) provides a service menu, comprising a number of links to service menus further down in the hierarchy or to IPDC services. The WAP portal (16) is provided with information relating to IPDC services by an IPDC operator (80). This information includes at least the name of the service, the IP address and the port number relating to each service. The information may additionally include a Network Information Table, IP/MAC Notification Table and Program Mapping Table, although this information may be provided to the mobile terminal instead by broadcast from a DVB transmitter (13).