The instant invention provides a method for diagnosing an infection in a subject by administering to the subject a compound suitable for imaging which binds to a thymidine kinase present in the infecting organism, and obtaining an image of the subject to determine the presence and location of the compound, wherein a localization of the compound is indicative that the subject has an infection. The system includes a memory, a bus controller communicatively coupled to the memory via a memory bus, and a MILS controller communicatively coupled to the bus controller via a host-side bus, the MILS controller configured for monitoring and controlling system transactions. Other features include the use of a toothed drive belt driven by a motor that may have a motor brake. At least one of the memory elements comprises a redundant memory element. The control processor generates and stores the input signal data packet within the dual-port RAM before asserting an interrupt signal to the main processing module. By providing two mean values and two different thresholds, it is possible to provide improved sensitivity to variations in the radio signal as a result of the mobile terminal moving quickly within a cell and less sensitivity to fluctuations of the radio signal at a mobile terminal that is substantially stationary and which are due to \u201cfading\u201d.