Alternative frequency strategy for DRM

Abstract

A radio transmission signal consisting of signal frames that comprise a dynamic data part and a quasi-static data part according to the present invention is characterized in that the dynamic data part of a respective frame contains an indicator showing in which following frame the quasi-static data part of this respective frame will be repeated. Therewith, an alternative frequency of e.g. a digital shortwave signal like a DRM signal can easily and satisfactorily be checked before a fast seamless switching to this alternative frequency can be performed. The inventive method to perform a seamless switching of a receiver from a first currently tuned frequency to a second alternative frequency is characterized by the step of receiving at least one set of samples from a respective signal transmitted on at least one second frequency during a time period during which said indicator assures that it is secure that only data that has been transmitted at least once is transmitted as signal on said first frequency to gather some information about said alternative frequency.

1 . A radio transmission signal consisting of signal frames that comprise a dynamic data part (DD) and a quasi-static data part (SD; SD 1 , SD 2 ), 
 wherein the dynamic data part (DD) of a respective frame contains an indicator showing in which following frame the quasi-static data part (SD; SD 1 , SD 2 ) of the respective frame will be repeated and    wherein said indicator directly shows a frame number of the following frame in which the quasi-static data part (SD) of the respective frame will be repeated.    
   
   
       2 . A radio transmission signal consisting of signal frames that comprise a dynamic data part (DD) and a quasi-static data part (SD; SD 1 , SD 2 ), 
 wherein the dynamic data part (DD) of a respective frame contains an indicator showing in which following frame the quasi-static data part (SD; SD 1 , SD 2 ) of the respective frame will be repeated, and    wherein said indicator indirectly shows the frame number of the following frame in which the quasi-data part (SD 1 , SD 2 ) of the respective frame will be repeated by validating the frame number indicated in the quasi-static data part (SD 1 , SD 2 ) of the respective frame.    
   
   
       3 . A radio transmission signal consisting of signal frames that comprise a dynamic data part (DD) and a quasi-static data part (SD; SD 1 , SD 2 ), 
 wherein the dynamic data part (DD) of a respective frame contains an indicator showing in which following frame the quasi-static data part (SD; SD 1 , SD 2 ) of this respective frame will be repeated, and wherein a gap part (GAP) in each frame which length might depend on a transmission frequency or a delay (Δt) between receivable alternative frequencies and which also comprise quasi-static data which will be repeated according to said indicator.