5G New Radio in Bullets_Chris Johnson

Table98-CodingofStart and Length IndicatorValue (SLIV) * 3GPP References: TS 38.214, TS 38.212, TS 38.331 3.6-4.2 FREQUENCY DOMAIN RESOURCE ALLOCATION * POSCH frequency domain resources can be allocated using Downlink Control Information(DC!) Fon11ats 1_0 and I_I. DCI is transferred to the UE using the PDCCH physical channel. The ·Frequency Domain Resource Assignment' field within these DCI Formats is used to specify the set ofalloeatcd Virtual Resource Blocks(VRB) * 3GPP has specified two downlinkresource allocation schemes Type 0 and Type I o DC! Format I_0: always usesType I o DCI Format I_I: uses eitherType 0 or Type I. The Base Station can use the PDSCH-Config parameter structure to configure 'resourceAl/ocation' with avalue of'rcsourceAllocationType0', 'rcsourccAllocationTypeI' or 'dynamicSwitch'. The 'dynamicSwitch' optionallows the Base Station touse the content ofthe DCI to dynamically change between resource allocation schemes. In this case, theMost Significant Bit(MSB) ofthe'Frequency Domain Resource Assignment' field within the DC! indicates the resource allocation type * The frequency domain resource allocationis applicable to a specific Bandwidth Part. The Base Station can use RRC signalling to configure up to4Bandwidth Parts per serving cell. Ifthe resource allocation is received using DCI Format I_0 within the Common Search Space for CORESET 0, then the resource allocation is applicable to the initial Bandwidth Part. Otherwise, resource allocations received using DCI Format I_0 areapplicableto the current active Bandwidth Part * DC! Format I_I can use the 'BandwidthPart Indicator' field to identify a specifie Bandwidth Part for the resource allocation. This can be used as a mechanism to changetheactive Bandwidth Part, ifthe UE has signalled its support for dynamic switching between Bandwidth Parts. The UE assumes thatthe resource allocation is applicable to the current active Bandwidth Part ifthe 'Bandwidth Part Indicator' field is not included within DCI Format I I 200

5GNR inBULLETS * The POSCH Mapping Type and Slot Offset columns are interpreted in the same way as the standardised tables * The Starting Symbol(S) and Length(L) are not explicitly shown within the configured look-up table. Instead they ajointly coded as the 'Start and Length Indicator Value' (SLIV). The SLIV is coded according to the following rules: if (L I)::, 7 then SLIV=l4x(L l)+S else SUV=14 x(14 - L+I)+(14- I S) where 0 < L :, 14 - S * The coding ofthe SLIV has been designed to minimise the range ofnumerical values, i.e. to minimise the number ofbits required to signal its value. The set ofvalues associated with the SUV is presented in Table 98 Length (L) I 2 3 4 5 6 7 8 9 10 II 12 13 14 0 0 14 28 42 56 70 84 98 97 83 69 55 41 27 I I 15 29 43 57 71 85 99 96 82 68 54 40 2 2 16 30 44 58 72 86 100 95 81 67 53 3 3 17 31 45 59 73 87 101 94 80 66 s€ 4 4 18 32 46 60 74 88 102 93 79 19 33 47 61 75 89 103 92 0 5 5 Sy 6 6 20 34 48 62 76 90 104 \"\"i� 7 7 21 35 49 63 77 91 8 8 22 36 50 64 78 CZ) 9 9 23 37 51 65 10 10 24 38 52 II II 25 39 12 12 26 13 13

5G NR in BULLETS 3.6.4.2.1 DOWNLINK RESOURCE ALLOCATION TYPE 0 * Downlink resource allocation type O can be signalled on the PDCCH using DC! Format I_ I. This type ofresource allocation uses a bitmap to indicate a set ofallocated Resource Block Groups (RBG), i.e. resources are allocated in terms ofRBG rather than individual Resource Blocks * A Resource Block Group (RBG) is a set ofcontiguous Virtual Resource Blocks (VRB) within a Bandwidth Part. The number of Resource Blocks within an RBG is dependent upon the Bandwidth Part size and the 'rbg-Size' information element provided within the PDSCH-Config shown in Table 88. The 'rbg-Size' can be configured with values ofeither 'config I' or 'config2'. The relationship between the Bandwidth Part size, the value of'rbg-Size' and the resultant RBG size is presented in Table 99 llandwidth Part Size Configuration I RBG Sizes Configuration 2 RBG Sizes (Resource Blocks~) (Resource Blocks) (Resource Bloc'ks) 2 4 8 I to 36 4 16 16 37 to 72 8 73 to 144 16 145 to 275 Table 99 - Resource Block Group (RBG) Sizes * Resource allocation type O always uses a 'non-interleaved' Virtual Resource Block (VRB) to Physical Resource Block (PRB) mapping. This means that VRB 'n' is mapped onto PRB 'n', i.e. the VE is effectively allocated PRB directly * The length ofthe bitmap used to provide the resource allocation depends upon the number ofRBG within the Bandwidth Part. There is I bit for each RBG. The RBGs at the lower and upper ends ofthe Bandwidth Part may contain fewer Resource Blocks. This depends upon the position ofthe Bandwidth Part within the set ofCommon Resource Blocks. Figure 171 presents some example Bandwidth Part positions to illustrate the possibility ofhaving smaller RBG at each end ofthe Bandwidth Part. Smaller RBG are generated when the end ofthe Bandwidth Part does not coincide with an integer multiple ofthe RBG size from the perspective ofCommon Resource Block numbering CommonResource Blocks within Base Station Channel Bandwidth Resource Block Group {RBG) size= 4 I::I 0 1 2 3 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 4RB 4RB 4RB 4RB 4RB Example 1: AllRBG within Bandwidth part have equal number of Resource Blocks Example positions 3RB 4RB 4RB 4RB 4RB Example 2:RBG at lower side of Bandwidth of o Bandwidth Part part has fewerResource Blocks I I2RB 4RB 4RB 4RB 3RB Example 3:RBG at lower and upper sides of Bandwidth part have fewerResource Blocks Figure 171 - Example sets of RBG within a Bandwidth Part * Figure 172 illustrates an example bitmap allocating a set ofRBG when the RBG size is 4. This example has a smaller RBG at the upper end ofthe Bandwidth Part. The allocated RBG do not need to be contiguous Example assumes Downlink Bandwidth Part Resource Block Group Size = 4 I-1-1-i-I-i-i-i-I-i-i-i-I-i-i-i-I-:-i -i-I-l -l -i -I-l -i -i -I -l -i -: -I -i -i 'I i i i i i i i ir-_-_-_-_-;_-__- -_-_-_-_-__- _- -__-_-_-_- _-)-- �������\"---y--- Resource Bl ck Groups � - _- -_-_-_-_-_-__- _- _- _- _- -_·_�__- -__- _- _- _- _- -_-_-_-_�?.-__- -_ .-: __- -_-_-_-:_-_-_-_-_-__- �_-_-_-_-_-__- -__- _- _- -_-_-_·_�__- ___- _-_-_-_-__- _- _- _- _- ;- _�-- _- _- _- _- _- -__- -__- _- _- -_�- --_- _- -__- -_-_�_-_--__- _- _- �- Bitmap signalled to the UE within the DC/ on the PDCCH Figure I72 - Use of a bitmap to allocate Resource Block Groups (RBG) within the active Bandwidth Part * 3GPP References: TS 38.214, TS 38.331, TS 38.211, TS 38.212 201