Frequency Hopping

4G/LTE

하나의 서브프레임과 다른 서브프레임 간에 일어나는 호핑  -> "inter subframe" hopping

하나의 서브프레임 안에서 일어나는 호핑 -> "intra subframe" hopping

인트라 서브프레임 호핑에서 하나의 슬롯과 다른 슬롯 간의 호핑 거리가 일정하지 않은 호핑도 있다.

자원 할당이 호핑되면서 flip되는 호핑도 있다. 즉, 하나의 슬롯의 자원 할당은 이전 슬롯의 미러 이미지 "mirroring"

 

기지국은 어떻게 업링크 호핑 패턴을 알 수 있을까? 네트워크가 모든 호핑 패턴을 결정하고, 지시대로 단말이 hop하도록 한다.

네트워크는 단말에게 SIB2 및 DCI 0을 통해 호핑 패턴의 디테일들을 알려준다.

 

 

38.213

8.1 

For a PUSCH transmission with frequency hopping in a slot, when indicated by msgA-intraSlotFrequencyHopping for the active UL BWP, the frequency offset for the second hop [6, TS 38.214] is determined as described in clause 8.3, Table 8.3-1 using msgA-HoppingBits instead of NUL,hop . If guardPeriodMsgA-PUSCH is provided, a first symbol of the second hop is separated by guardPeriodMsgA-PUSCH symbols from the end of a last symbol of the first hop; otherwise, there is no time separation of the PUSCH transmission before and after frequency hopping. If a UE is provided with useInterlacePUCCH-PUSCH in BWP-UplinkCommon, the UE shall transmit PUSCH without frequency hopping. A PUSCH transmission uses a same spatial filter as an associated PRACH transmission.

 

9.2.1 PUCCH Resource Sets

...

 

38.214

6.1.2 Resource allocation

(p124)

-     When frequency hopping is enabled, the frequency offset between two frequency hops can be configured by higher layer parameter frequencyHoppingOffset.

 

6.2.1.1 UE SRS frequency hopping procedure(p140)

 

6.3 UE PUSCH frequency hopping procedure

6.3.1 Frequency hopping for PUSCH repetition Type A

For PUSCH repetition Type A (as determined according to procedures defined in Clause 6.1.2.1 for scheduled PUSCH, or Clause 6.1.2.3 for configured PUSCH), a UE is configured for frequency hopping by the higher layer parameter frequencyHoppingDCI-0-2 in pusch-Config for PUSCH transmission scheduled by DCI format 0_2, and by frequencyHopping provided in pusch-Config for PUSCH transmission scheduled by a DCI format other than 0_2, and by frequencyHopping provided in configuredGrantConfig for configured PUSCH transmission. One of two frequency hopping modes can be configured:

-     Intra-slot frequency hopping, applicable to single slot and multi-slot PUSCH transmission and each of multiple PUSCH transmissions scheduled by a DCI if the higher layer parameter pusch-TimeDomainAllocationListForMultiPUSCH is configured.

-     Inter-slot frequency hopping, applicable to multi-slot PUSCH transmission.

...

In case of intra-slot frequency hopping, the starting RB in each hop is given by:

                                                            ,

where i=0 and i=1 are the first hop and the second hop respectively, and  is the starting RB within the UL BWP, as calculated from the resource block assignment information of resource allocation type 1 (described in Clause 6.1.2.2.2) or as calculated from the resource assignment for MsgA PUSCH (described in [6, TS 38.213]) and is the frequency offset in RBs between the two frequency hops. The number of symbols in the first hop is given by , the number of symbols in the second hop is given by , where NsymbPUSCH,s  is the length of the PUSCH transmission in OFDM symbols in one slot.

 

In case of inter-slot frequency hopping, the starting RB during slot  is given by:

                                          

 

 

6.3.2 Frequency hopping for PUSCH repetition Type B