5G/NR - Resource Allocation                             Home : www.sharetechnote.com

 

 

 

 

 

Resource Allocation

 

As in LTE, in NR as well Resource Allocation should be defined both in Time domain and Frequency Domain. In LTE, we didn't care much about the time domain resource allocation since they are assigned by a fixed/predefined rule, but in NR the time domain resource allocation is determined by much more complicated rule than in LTE whereas freuqency domain resource allocation is almost same as in LTE.

 

Following is the list of topics related to the resource allocation in Time Domain.

As mentioned above, frequency domain resource allocation is very similar to LTE. Mainly determined by bitmap or RIV depending of Resource Allocation Type. This part will be described in a separate page titled Resource Allocation Type.

 

 

 

PDSCH - Time Domain Allocation (DCI - PDSCH Timing)

 

 

Following is the illustration showing the Time Domain resource allocation for PDSCH based on 38.214 - 5.1.2.1 Resource allocation in time domain

 

 

Following is the RRC parameters determining k0. SLIV determination is a pretty complicated process. so I created a separate page for this, refer to this page.  PDSCH-TimeDomainResourceAllocation is an IE(Information Element) of PDSCH-Config and PDSCH-ConfigCommon. It is defined as an element (a kind of array element) of an IE called pdsch-AllocationList.  Once this array(pdsch-AllocationList) is defined in RRC message, which elements of the array is used for each PDSCH scheduling is determined by the field called Time domain resource assignment in DCI 1_0 and DCI 1_1.

 

 

PDSCH-TimeDomainResourceAllocation ::= SEQUENCE {

   k0                                  INTEGER(0..32)        OPTIONAL, -- Need S

   mappingType                         ENUMERATED {typeA, typeB},

   startSymbolAndLength                INTEGER (0..127)  // SLIV

}

 

 

Example 1 >

 

This example is based on 38.523-3 7.1.2.2.2.

 

 

 

Example 2 >

 

This example is based on 38.523-3 7.1.2.2.2.

 

 

 

 

PDSCH - Ack/Nack Timing

 

PDSCH-Ack/Nack Timing defines the time gap between PDSCH transmission and the reception of the PUCCH that carries ACK/NACK for the PDSCH.

 

 

 

PUCCH-Config ::=        SEQUENCE {

...

    dl-DataToUL-ACK        SEQUENCE (SIZE (8)) OF INTEGER (0..15)   OPTIONAL,   -- Need M

...

}

 

 

 

PUSCH - Time Domain Allocation

 

 

Following is the illustration showing the Time Domain resource allocation for PUSCH based on 38.214 - 6.1.2.1 Resource allocation in time domain 

 

 

 

Following is the RRC parameters determining k2. SLIV determination is a pretty complicated process. so I created a separate page for this, refer to this page.

 

PUSCH-TimeDomainResourceAllocation ::=  SEQUENCE {

    k2                                  INTEGER (0..32)                          

    mappingType                         ENUMERATED {typeA, typeB},

    startSymbolAndLength                INTEGER (0..127) // SLIV

}

 

 

 

Reference

 

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