A9.1.1 Blocking level determination methodology

The blocking parameters of a standard are specified for specific values used for compliance testing, which do not always correspond to typical operational values. In particular, blocking values are specified for desensitisation values which may not correspond to the desired operational value for specific studies (e.g. 1 dB for BS and 3 dB for UE). It is therefore sometimes necessary to translate the Blocking Level IOOB-STANDARD defined by the standard for a desensitisation DSTANDARD into the corresponding Blocking Level IOOB-TARGET for another desensitisation DTARGET.

Coexistence analysis are conducted for a standard that provides a maximum power (Blocking Level) of an interfering signal received outside of the in-band, for a given frequency offset between the wanted signal and the interfering signal. This absolute blocking level IOOB-STANDARD is specified in the standard for a specific desensitisation D_STANDARD. This is the case for the blocking specifications in UMTS and LTE standards (3GPP TS 25 101 [5], TS 25 104 [3], TS 36 101 [1] and TS 36 104 [2]). It is also the case for the blocking specifications for the 3rd adjacent channel and the following channels in GSM (3GPP TS 45 005 [21]).

For studies considering C/(N+I) protection ratio, an example of blocking specifications for the first 2 adjacent channels can be found in the GSM standard (3GPP TS 45 005 [21]).