nslot whereas for a UE-specific search spaces Yp,nslot = (ApY),, mod D, Yp,-1 NRNTI, Ap = 39827, 39829, or 39839 p mod 3 = 0, 1, or 2, respectively. In the preceding expression, D = 65537; NCCE,p is the number of CCEs, numbered from 0 to NCCE,P - 1, in CORESET p; and NCI denotes the car- rier indicator field value, if the UE is configured via RRC signaling with a carrier indicator field in the serving cell on which the PDCCH is monitored; otherwise, including for any common search space NCI = 0. Furthermore, ms,nc = 0, M(L) p,s,ncl - 1, where M(L) p,s,ncl New Radio Access Physical Layer Aspects (Part 2) 473 CCE 0 CCE 0 REG bundle 0 REG bundle 0 REG bundle 1 CCE 1 REG bundle 1 REG bundle 6 REG bundle 6 REG bundle 7 REG bundle 7 CORESET CORESET REG 0REG 1REG 2 CCE 0 CCE 0 REG bundle 0 REG bundle 0 REG bundle 1 REG bundle 1 REG 3 REG bundle 6 REG bundle 6 REG bundle 7 REG bundle 7 CORESET CORESET Figure 4.24 Illustration of alternative PDCCH mapping rules: (A) PDCCH candidate-level, (B) CCE-level, (C) REG bundle-level, and (D) REG-level. number of PDCCH candidates that the UE is supposed to monitor at aggregation level L in a search space set S in a serving cell corresponding to NCI. For any common search space, max(M(D) p,s,ncl )=MM = whereas for a UE-specific search space, denotes the max- imum of M over the configured values of NCI for a CCE aggregation level L of search p,s,ncl space set S in CORESET p; the RNTI value used for NRNTI is the C-RNTI [8]. Example PDCCH search spaces at various aggregation levels are shown in Fig. 4.25. Physical CCE index 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 2324 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 4 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 Virtual CCE index 4 5 6 7 8 9 10 11 12 13 14 15 16 17.18-19 20 21 22 23 24 25 26 27 28 29 30 31 Aggregation level 16 Aggregation level 8 Aggregation level 4 Aggregation level 2 Aggregation level 1 Figure 4.25 Example PDCCH search spaces at various aggregation levels. New Radio Access Ph