Page 106 - Kaleidoscope Academic Conference Proceedings 2020

2020 ITU Kaleidoscope Academic Conference

occasions is indicated by a dynamic 2-D bitmap in DPCI. whether it overlaps with eMBB transmission. For BPC, once
More specifically, the bit construction of DPCI is illustrated the resource of URLLC overlaps with that of eMBB, the
as follows. URLLC UE will perform P-dB power boosting, i.e., 6 dB.
However, the eMBB transmission will cause quite different
 Q bits are used for indicating which time domain interference on URLLC time-frequency resources under
occasion is occupied, where ‘Q’ equals the number of some situations. For example, as shown in Figure 5, the
occasions in the time domain per RUR. transmission power of different eMBB UEs is different in the
same RUR, and the proportion of overlapping resources to
 Cm×n is 2-D bitmap for frequency domain indication, the total resources of URLLC services is different in
i.e., the occupied time domain occasions are divided different RURs. A fixed value of power boosting will not
into ‘a×b’ portions, each portion is indicated by a bit in only lead to insufficient or serious power waste for URLLC
the 2-D bitmap, wherein a represents number of transmission, but also affect the transmission performance of
occupied time domain occasions and b represents normal eMBB services.
frequency domain granularity. Both of them are
determined according to the indication of Q bits Compared with fixed power adjustment according to
dynamically. resource multiplexing, the following two points are
enhanced in ROPC: 1) defining different power control
Under the example shown in Figure 4, Q=7, a = 2 and b=10, parameters for different resource groups; 2) boosting power
then the total bit-number is 27. Compared with BCI, which according to the proportion of overlapping resources to the
requires 28bits, this method can make the frequency domain total resources of URLLC services. More details are
indication granularity (FDIG) finer with the same number of provided on the above two enhancements in the following
bits. This could reduce the false cancellation probability for subsections.
a better protection of eMBB PUSCH. As shown in Table 1,
as long as the number of occupied time domain occasions 3.2.1 Different power control parameters for different
(OTDOs) is less than 5, the minimum frequency domain resource groups
indication granularity for each time domain occasion of
DPCI is finer than that of BCI. In an RUR, multiple groups of a time-frequency resource can
be indicated by gNB to the URLLC UE. Different groups of
time-frequency resource correspond to different power
control parameter sets. The URLLC transmission power is
determined according to the power control parameter set
corresponding to the group of time-frequency resource it
overlaps with eMBB.
F
O1 O2 O3 O4 O5 O6 O7 O2 O5 As shown in Figure 6, the control information of ROPC
T Resource scheduled Cancelation resource includes at least one time-frequency resource indication field.
for UL URLLC indicated by DPCI Each time-frequency resource indication field can indicate a
Resource cancelled
by UL CI falsely group of time-frequency resources. The power control
Figure 4 – Resource indicated by dynamic 2-D bitmap parameters for each group of time-frequency resources will
be configured via radio resource control signaling. If the
Table 1 – Minimum indication granularity with different resource scheduled for URLLC transmission overlaps with
number of the occupied time domain occasions more than one group of time-frequency resources,
transmission power will be calculated based on each power
OTDOs 1~7 control parameter respectively, and a higher one or an
number
BCI average value will be selected.
FDIG 1
4
OTDOs 1 2 3 4 5 6 7
DP number
CI FDIG 1 ≤ 1 1 ≤ 1 ≤ 1 ≤ 1 1
21 10 7 5 4 3 3 RUR #1 RUR #2 RUR #3
Resource scheduled for UL Resource scheduled
3.2 Design for ROPC eMBB with PC parameter set A for UL URLLC
Resource scheduled for UL
eMBB with PC parameter set B
In order to ensure the flexibility of URLLC transmission, it’s Figure 5 – Various situations of overlapping between the
better for gNB to schedule the most appropriate time- URLLC PUSCH and the eMBB PUSCH
frequency resources for the URLLC UE without caring

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