1. Way forward on the SFN channel model CATT,…. R4-153130 3GPP TSG-RAN WG4 Meeting #75 Fukuoka, Japan, 25 – 29 May, 2015 Agenda Item: 9.2.1

2. SFN channel model Two-tap dynamic channels –There are two taps with independent time-variant parameters of Doppler shifts; Relative power; Timing difference between two taps; we assume that is the distance between the two RRHs, is RRH Railway track distance, is RRH height, all in meters; is the velocity of the train in m/s, c is the velocity of light in m/s, is time in seconds. is the carrier frequency.

3. SFN channel model  Definition of taps There are two options can be considered for the definition of taps: Option 1: Define the taps with respect to the serving RRH. The path1 is always corresponding to the with RRH with odd number The path2 is always corresponding to the with RRH with even number Option 2: Define the taps with respect to their arriving time. The first arriving path is defined as path 1 which is also always stronger. The second arriving path is defined as path2.

4. SFN channel model  Tap delay There are two options for the definition of time delays for taps. –Option 1: Each tap has a varying time delay with respect to the time when UE is away from RRH. If define the taps with respect to the serving RRH. The time delay of tap 1 is The time delay of tap 2 is

5. SFN channel model  Tap delay There are two options for the definition of time delays for taps. –Option 2: Fixing the first received tap with time delay of 0. [Corresponding to option 1 in tap definition] Reference R4-152369

6. SFN channel model  Tap power –Option 1: the taps with respect to the serving RRH. then –Let and be the power of tap1 and tap 2 respectively, if define the taps with respect to the serving RRH. then

7. SFN channel model  Tap power –Option 1a: Normalize the received power of each tap with respect to the average total received power. where is the average total received power, –Option 1b: Using relative power with respect to the received power of a certain E.g. The maximum power that could be possible achieved as 0dB.

8. SFN channel model  Tap power –Option 2: the taps with respect to the arriving time

9. SFN channel model  Doppler shifts  Option 1a:

10. SFN channel model Option 1b: (CATT: R4-53129)

11. SFN channel model Option 1c: (Qualcomm: R4-151587)

12. SFN channel model Option 2: (CATT: R4-153129)

13. SFN channel model The value of the parameters are ParameterValue Ds[1500 m] Dmin[100m] h RRH [15m] v350 km/h fdfd 875 Hz