The term “Blocking” is used in SEAMCAT to describe the capability of the victim receiver to receive a wanted modulated signal without exceeding a given degradation due to the presence of an unwanted input signal on a frequency other than the frequency of the wanted signal.
It has to be noted that most standards and specifications distinguish between the receiver selectivity given as Adjacent Channel Selectivity (ACS) for frequency offsets close to the centre frequency of the VLR, and Blocking (a term often associated with desensitisation) for frequency offsets far away from the centre frequency of the VLR. It is assumed that the receiver blocking performance is flat over the bandwidth of the interfering signal.