Content for TR 38.854 Word version: 18.0.0

5.2.1 Unidirectional deployments p. 10

For the unidirectional scenario RAN4 will consider SFN scenario. Hence, one panel per RRH pointed to the same direction for all RRHs (Figure 5.2.1-1).

Copy of original 3GPP image for 3GPP TS 38.854, Fig. 5.2.1-1: HST scenario with one panel per RRH pointing to the same direction for all RRHs

Figure 5.2.1-1: HST scenario with one panel per RRH pointing to the same direction for all RRHs
(⇒ copy of original 3GPP image)

For the unidirectional scenario the following unidirectional deployment scenario in Table 5.2-1 will be prioritized:

Table 5.2-1: Assumed deployment parameters for unidirectional scenario.

Parameter	Value
Ds and Dmin	Scenario 2: Ds = 700m and Dmin = 10m Scenario 4: Ds = 700m and Dmin = 150m Tunnel scenario: Ds=700m and Dmin = 1m
RRH height	Scenario 2 and 4: 15m Tunnel Scenario: 5.3m (Note 1)
Number of RRH sites per BBU	4
Number of RRH panels per RRH sites	1 (i.e. unidirectional) (Note 2)
Number of analog beams per RRH panel	1 or 2 (Note 3)
RRH panel orientation	Option 1: RRH panel boresight pointed to the railway at the direction of Ds (projection of the neighboring RRH on the railway). Option 2: other options not precluded
Analog beam orientation	Based on companies' selection for better performance
NOTE 1: RRH height for single track railway tunnel. For two-track railway tunnel, RRH height is 7.4m NOTE 2: For JT for all channels, 1 beam per RRH panel is considered. NOTE 3: For DPS, 1 or 2 analog beams per RRH panel can be considered.

Number of Beam for unidirectional RRH deployment, Scenario 2:

For scenario 2, unidirectional, RRH parameter: 1 beam per RRH panel; and
For scenario 2, unidirectional, UE parameter:
1. 1 beam per panel; and
2. 2 panels assumed to be implemented in the UE side; and
3. Only the one active panel per UE can be used for Tx and Rx; and FFS whether another panel can be used for beam search

RRH switching point for unidirectional RRH deployment, Scenario 2, Figure 5.2.1-2:

RRH switching point is where the UE switches from the source RRH beam to the target RRH beam based on maximizing SNR among detected beams.

Copy of original 3GPP image for 3GPP TS 38.854, Fig. 5.2.1-2: RRH switching point for unidirectional RRH deployment.

Figure 5.2.1-2: RRH switching point for unidirectional RRH deployment.
(⇒ copy of original 3GPP image)

Number of Beam for unidirectional RRH deployment, Scenario 4:

For scenario 4, unidirectional, RRH parameter:
1. 1 beam per RRH panel; or
2. 2 beams per RRH panel; or
3. 3 beams per RRH panel; or
4. 4 beams per RRH panel.

Note that uneven separation between beams can be considered.

RAN4 agreed that at least 2 beams per RRH panel is considered. Other options are not precluded, and it is FFS whether there are benefits of implementing more beams per RRH panel.

For scenario 4, unidirectional, UE parameter:
1. 1 beam per UE panel; or
2. 2 beams per UE panel; or
3. 7 beams per UE panel.

RAN4 assumes 2 panels to be implemented in the UE side. Only the one active panel per UE can be used for Tx and Rx; and FFS whether another panel can be used for beam search.

RAN4 decided that at least option a) of having 1 beam per panel is considered. Other options are not precluded, and it is FFS whether there are benefits of implementing more beams per UE panel.

Number of Beam for unidirectional RRH deployment in Tunnel scenario shall follow similar setting as in Scenario 2:

For Tunnel scenario, unidirectional, RRH parameter: 1 beam per RRH panel; and
For Tunnel scenario, unidirectional, UE parameter:
1. 1 beam per panel; and
2. 2 panels assumed to be implemented in the UE side; and
3. Only the one active panel per UE can be used for Tx and Rx; and FFS whether another panel can be used for beam search
RRH switching point for unidirectional RRH deployment, Tunnel scenario, Figure 5.2.1-2 with Ds_offset could be shorter than that in Scenario 2.