B.2.4 Two-tap propagation conditions for CQI tests
38.521-43GPPNRPart 4: PerformanceRadio transmission and receptionRelease 17TSUser Equipment (UE) conformance specification
For Channel Quality Indication (CQI) tests, the following additional multi-path profile is used:
in continuous time
representation, with 
the delay, a constant value of a and
the Doppler frequency. The same h(t,τ) is used to describe the fading channel between every pair of Tx and Rx.