A8.7 RECEIVER ATTENUATION AS ELEMENT OF BLOCKING RESPONSE

Based on the definition and measurement procedure of blocking, it is possible to obtain the receiver attenuation parameter a_VLR(Df) from the following fundamental relationships between wanted and unwanted signals, receiver sensitivity and noise, as observed when blocking event is triggered:

Figure 397: Relationship between signal levels when blocking occurs (Protection Ratio and Sensitivity modes)

Note: the coloured arrows show the relationship of the input parameters used for the calculation of the resulting blocking response (a_VLR(∆f)) and described in the sections above.

Examples:

VLR      noise floor:                   -114 dBm

            sensitivity:                    -98 dBm

            C/(N+I):                         16 dB

            I/N:                               -6 dB

            (N+I)/N                          1 dB

a)         blocking mode "Sensitivity"
            limit:                            -45 dBm

b)         blocking mode "Protection ratio"           

            limit:                            52 dB

75 dB