Method and apparatus for SSB synchronization

Abstract

An apparatus, comprising at least one processor; and at least one memory storing instructions that, when executed by the at least one processor, cause the apparatus at least to receive at least an indication indicating an activation of a first TCI state associated with a first SSB, and a second TCI state associated with a second SSB, wherein the first SSB is received from a first TRP, and the second SSB is received from a second TRP; determine a time difference between the first occurring instance of the first SSB and the first occurring instance of the second SSB; and synchronize with the first occurring instance of the first SSB and after a first delay with an occurring instance of the second SSB, wherein the first delay is based at least in part on the determined time difference between the first occurring instance of the first SSB and the first occurring instance of the second SSB.

Description

METHOD AND APPARATUS FOR SSB SYNCHRONIZATIONTECHNICAL FIELD

[0001] Various example embodiments relate to SSB synchronization.BACKGROUND

[0002] This section illustrates useful background information without admission of any technique described herein representative of the state of the art.

[0003] 3GPP RAN4 TS38.133 discusses Transmission Configuration Indicator, TCI, state switching delay requirements for unified TCI states and addresses that when the Synchronization Signal Blocks, SSB, which are used for fine time / frequency tracking for the two activated downlink TCI states are overlapping or adjacent, a UE is not expected to be able to do the Time / Frequency, T / F, tracking for each of the first SSBs after processing a Medium Access Control Control Element, MAC-CE.

[0004] In such a case, the UE would need an additional delay, e.g. of an additional SSB periodicity, to be able to synchronize with both SSBs. This might be because the UE may be receiving the two SSBs from different directions with different panels, and when the UE is not capable of simultaneous reception with two panels, the UE would need to switch the panel to be able to synchronize with both SSBs. When the SSBs are overlapping or adjacent to each other, the UE would not have time to switch the panel, or time for internal operations, so that it would be able to measure both SSBs which are overlapping or adjacent.

[0005] The present disclosure provides for determining the overlap or adjacency of the SSBs the UE is using for synchronizing and for determining conditions in which no additional switching delay of one SSB period is needed for synchronizing with the SSBs during TCI state switching and conditions in which the UE is allowed additional time in TCI state switching.SUMMARY

[0006] The scope of protection sought for various embodiments of the invention is set out by the independent claims. The embodiments and features, if any, described in this specification that do not fall under the scope of the independent claims are to be interpreted as examples useful for understanding various embodiments of the invention.

[0007] According to a first example aspect, there is provided an apparatus as defined by appended claim 1.

[0008] According to a second example aspect, there is provided an apparatus asdefined by appended claim 13.

[0009] According to a third example aspect, there is provided a method as defined by appended claim 20.

[0010] According to a fourth example aspect, there is provided a method as defined by appended claim 21.

[0011] According to a fifth example aspect, there is provided an apparatus as defined by appended claim 22.

[0012] According to a sixth example aspect, there is provided an apparatus as defined by appended claim 23.

[0013] According to a seventh example aspect, there is provided a computer program as defined by appended claim 24.

[0014] According to an eighth example aspect, there is provided a non-transitory computer readable medium as defined by appended claim 25.

[0015] According to a ninth example aspect, there is provided a computer readable medium as defined by appended claim 26.

[0016] According to a tenth example aspect, there is provided a system as defined by appended claim 27.

[0017] According to an eleventh example aspect, there is provided a system as defined by appended claim 28.

[0018] Any foregoing memory medium may comprise a digital data storage such as a data disc or diskette, optical storage, magnetic storage, holographic storage, opto-magnetic storage, phase-change memory, resistive random access memory, magnetic random access memory, solid-electrolyte memory, ferroelectric random access memory, organic memory or polymer memory. The memory medium may be formed into a device without other substantial functions than storing memory or it may be formed as part of a device with other functions, including but not limited to a memory of a computer, a chip set, and a sub assembly of an electronic device.

[0019] Different non-binding example aspects and embodiments have been illustrated in the foregoing. The embodiments in the foregoing are used merely to explain selected aspects or steps that may be utilized in implementations. Some embodiments may be presented only with reference to certain example aspects of the invention. It should be appreciated that corresponding embodiments may apply to other example aspects as well.BRIEF DESCRIPTION OF THE DRAWINGS

[0020] For a more complete understanding of example embodiments, reference is now made to the following descriptions taken in connection with the accompanying drawingsin which:

[0021] Fig 1 shows a principle view of SSBs in an example embodiment;

[0022] Fig. 2 shows a further principle view of SSBs in an example embodiment;

[0023] Fig. 3 shows a further principle view of SSBs in an example embodiment;

[0024] Fig. 4 shows a further principle view of SSBs of an example embodiment;

[0025] Fig 5 shows a flow chart of a method of an example embodiment;

[0026] Fig. 6 shows a flow chart of a method of an example embodiment;

[0027] Fig. 7 shows a flow chart of a method of an example embodiment; and

[0028] Fig 8 shows a block diagram of an apparatus of an example embodiment.DETAILED DESCRIPTION

[0029] An example embodiment and its potential advantages are understood by referring to Figs. 1 through 8 of the drawings. In this document, like reference signs denote like parts or steps.

[0030] Fig. 1 shows a principle view of Synchronization Signal Blocks, SSB, in an example embodiment. In an example embodiment, Medium Access Control Control Element, MAC-CE, based, Transmission Configuration Indicator, TCI, state activation is performed after receiving MAC-CE command to activate one or more TCI states to the active TCI state list. During the MAC-CE activation delay, the User Equipment, UE, will perform fine time / frequency tracking using the first SSB with the correct Quasi co-location, QCL, relationship after the UE has processed the MAC-CE command. The UE receives at least an indication indicating an activation of the first TCI state associated with a first Synchronization Signal Block, SSB, and a second TCI state associated with a second SSB.

[0031] Fig 1 shows a first SSB 100 and a second SSB 200. Fig. 1 shows a first occurring instance of the first SSB 100 and a first occurring instance of the second SSB 200. In an example embodiment, User Equipment, UE, needs a certain distance, i.e. a time difference, the minimum of which is a predetermined first time period, between the first occurring instance of the first SSB 100 and the first occurring instance of the second SSB 200 to be able to synchronize with the first occurring instance of both SSBs.

[0032] In an example embodiment, the predetermined first time period comprises the minimum time needed for the receiving UE to switch panels and / or carry out further internal operations. In a further example embodiment, the predetermined first time period is determined at least in part based on at least one capability of the apparatus. In a further example embodiment, the UE communicates the value of the predetermined first time period to the network.

[0033] In an example embodiment, the UE synchronizes with the first occurringinstance of the first SSB 100 and after a first delay with the first or a subsequent occurrence of the second SSB 200. The length of the first delay is dependent on the time difference between the first occurring instance of the first SSB 100 and the first occurring instance of the second SSB 200, i.e. the first delay is extended if the time difference is too small.

[0034] In an example embodiment, the first 100 and the second 200 SSB are received from two Transmission and Reception Points, TRP, and the time difference is in an example embodiment needed to allow time for the UE to switch from the panel receiving from one TRP to the panel receiving from another TRP, when simultaneous reception with two panels is not supported. In a further example embodiment, in addition to or instead of the time required for panel switch, the time difference 10 is required to cover other UE internal processing. In a further example embodiment, the UE communicates the needed time difference to the network.

[0035] In an example embodiment, the first 100 and the second 200 SSB comprises a plurality of signals 110-140, 210-240. In an example embodiment, the First 100 and the second 200 SSB comprise Primary Synchronization Signal 110, 210, PSS, a first Physical Broadcast Channel 120,220, PBCH, signal, a Secondary Synchronization Signal 130,230 SSS, and a second PBCH signal 140,240.

[0036] In an example embodiment shown in Fig. 1 , the time difference 10 between the first occurring instance of the first SSB 100 and the first occurring instance of the second SSB 200 comprises the time from an end of the first SSB 100 to the start of the second SSB 200.

[0037] Fig. 2 shows a further principle view of SSBs in an example embodiment. Fig. 1 shows a first occurring instance of the first SSB 100 and a first occurring instance of the second SSB 200. The first 100 and the second 200 SSB of Fig. 2 are similar to those discussed hereinbefore with respect to Fig. 1 .

[0038] Fig. 2 shows a situation in which there is no or little time difference 10 between the end of the the first occurring instance of the first SSB 100 to the start of the the first occurring instance of the second SSB 200. In an example embodiment, for synchronizing with the first SSB associated to a TCI state after decoding the TCI state activation MAC-CE, the UE actually only needs to read the PSS 110 and SSS 130 of the first SSB and does not need the first or second PBCH 120,140.

[0039] In an example embodiment in which the SSBs are adjacent to each other as shown in Fig. 2, the UE may switch the panel and / or carry out further internal operations during the PBCH 140 of the first SSB 100 and the time difference 10 needed between the first occurring instance of the first SSB 100 and the first occurring instance of the second SSB 200 comprises the time from an end of the Secondary Synchronization Signal 130, SSS, of thefirst SSB 100 to a start of a Primary Synchronization Signal 210, PSS, of the second SSB 200.

[0040] In a further example embodiment, the time difference 10 needed between the first occurring instance of the first SSB 100 and the first occurring instance of the second SSB200 comprises the time from an end of the PSS 110 of the first SSB 100 to a start of the PSS201 of the second SSB 200. In a still further example embodiment, the the time difference 10 needed between the first occurring instance of the first SSB 100 and the first occurring instance of the second SSB 200 comprises the time from an end of a PSS 110 of the first SSB 100 to a start of a SSS 230 of the second SSB 200.

[0041] Fig. 3 shows a further principle view of SSBs in an example embodiment. Fig.3 shows example scenarios 300a, 300b, 300c of SSBs that have been sent in adjacent symbols as shown in Fig. 2 arriving somewhat overlapping or with some distance therebetween depending on the Receive Timing difference, RTD. In the example 300a, the RTD has a length of 1 symbol and the first SSB 100 has been delayed. In the example 300b, the RTD is 0.5 symbols and the first SSB 100 has been delayed. In the example 300c, the RTD is 1 symbol, and the second SSB 200 has been delayed. In some of these examples, the distance between SSS of the first SSB and PSS of the second SSB becomes smaller and may not anymore be sufficient for panel switch. In an example embodiment, the distance between transmitting the first SSB 100 and the second SSB 200 is larger than the minimum time required for panel switching and / or internal operations of the UE.

[0042] Fig. 4 shows a further principle view of SSBs of an example embodiment. Fig.4 shows the first 100 and the second 200 SSB as they are sent at 400a and as they are received at 400b. In an example embodiment, the network does not know the RTD that is experienced by the UE, so the network assumes a Maximum Receive Timing Difference, MRTD, as the receive timing difference.

[0043] In an example embodiment, the first occurring instance of the first SSB 100 and the second occurring instance of the second SSB 200 are sent at 200a with a second delay 20. In an example embodiment, the second delay is defined as the time between predetermined signals of the first SSB 100 and the second SSB 200, wherein the second delay comprises the sum of a Receive Timing Difference, RTD and the predetermined first time period, i.e. the minimum time needed for the receiving UE to switch panels and / or carry out further internal operations. In an example embodiment, the UE has communicated the minimum time needed corresponding to the first time period to the network.

[0044] In an example embodiment, the network knows the RTD and uses the known value. In a further example embodiment, the network estimates the RTD. Ina still further example embodiment, the network uses the MRTD as the RTD value.

[0045] In an example embodiment shown in Fig. 4, the network sends the firstoccurring instance of the first SSB 100 and the second occurring instance of the second SSB 200 with a second delay 20 and they are received at 400b with the first SSB being delayed by RTD 30 and the time difference 10 for example from the end of the SSS of the first SSB 100 to the start of the PSS of the second SSB 200 corresponds to the first time period, i.e. the minimum time needed.

[0046] In an example embodiment, the second delay 20 applies at the network side and it is the time distance between transmitting the predetermined signals, or parts of the first occurrence of the first 100 and the second 200 SSB so that they will not to be considered adjacent or overlapping when they arrive at the UE, as long as RTD is within MRTD.

[0047] In an example embodiment, the second delay 20 is the time from a predetermined part of the first occurring instance of the first SSB to a predetermined part of the first occurring instance of the second SSB and selected from the group of: the time from an end of the first SSB to the start of the second SSB; the time from the end of the SSS, of the first SSB to a start of the PSS, of the second SSB; the time from the end of the PSS of the first SSB to the start of the PSS of the second SSB; and the time from the end of the PSS of the first SSB to the start of the SSS of the second SSB.

[0048] In an example embodiment, regarding the TCI state switching delay, the UE is allowed additional delay in TCI state switching delay of two TCI states only if the predetermined signals, or parts of the first occurrence of the first 100 and the second 200 SSB are received less the first time period away from each other. Otherwise, a longer delay is allowed as the SSBs are considered overlapping and the UE is not able to synchronize with both of them on the same occurrence.

[0049] From network point of view, this means that the network can assume a shorter TCI state switching delay in case the distance between for example the SSS of the first SSB and the PSS of the second SSB is at least the predetermined first time period when the first occurrence of the first 100 and the second 200 SSB is transmitted. In such an example embodiment, the UE synchronizes with both SSBs using the first occurrence and does not need additional SSB periodicity to complete the dual TCI state switch. As a result, the network can start scheduling the UE after the shorter delay. Otherwise, the network needs to assume a longer TCI state switching delay and can only start scheduling the UE after the longer delay.

[0050] Fig. 5 shows a flow chart of a method of an example embodiment. Fig. 5 shows a method of an example embodiment for a User Equipment, UE. The method comprises501. Receiving at least an indication indicating an activation of a first Transmission Configuration Indicator, TCI state associated with a first Synchronization Signal Block, SSB, and a second TCI state associated with a second SSB, whereinthe first SSB is received from a first Transmission and Reception Point, TRP, and the second SSB is received from a second TRP.502. Determining a time difference between the first occurring instance of the first SSB and the first occurring instance of the second SSB.503. Synchronizing with the first occurring instance of the first SSB and after a first delay with an occurring instance of the second SSB, wherein the first delay is based at least in part on the determined time difference between the first occurring instance of the first SSB and the first occurring instance of the second SSB

[0051] In an example embodiment, the determined time difference between the first occurring instance of the first SSB and the first occurring instance of the second SSB comprises the time from a predetermined part of the first SSB to a predetermined part of the second SSB. In an example embodiment, selected from the group of the time from an end of the first SSB to the start of the second SSB; the time from an end of a Secondary Synchronization Signal, SSS, of the first SSB to a start of a Primary Synchronization Signal, PSS, of the second SSB; the time from an end of a PSS of the first SSB to a start of a PSS of the second SSB and the time from an end of a PSS of the first SSB to a start of a SSS of the second SSB.

[0052] In an example embodiment, the predetermined first time period comprises the time required for panel switching or further internal processing at the UE, i.e. it is the time the UE needs between synchronising with the first SSB and the second SSB. In an example embodiment, the predetermined first time period is determined at least in part based on at least one capability of the apparatus.

[0053] In an example embodiment, the UE communicates or has communicated the value of the first time period to the network. In such an example embodiment, the network then subsequently knows the value of the predetermined first time period.

[0054] In an example embodiment, the first delay is the delay between synchronizing with the first SSB and the second SSB. If the time determined difference is larger than the first time period, i.e. the minimum time the UE needs, the UE can synchronize with the first occurrence of both the first and the second SSB, If the determined time difference is smaller than the predetermined time difference, the first delay is extended. In an example embodiment, the first delay is extended by a delay of a single SSB periodicity.

[0055] Fig. 6 shows a flow chart of a method of an example embodiment. Fig. 6 shows a method of an example embodiment for a network device. The method comprises601. Determining a second delay;602. Sending at least an indication indicating an activation of a first, Transmission Configuration Indicator, TCI state associated with a first Synchronization Signal Block,SSB, and a second TCI state associated with a second SSB, wherein the first occurring instance of the first SSB and the first occurring instance of the second SSB are sent with the second delay.603. Sending after a predetermined second time period at least one of one or more PDCCH transmissions associated with the first TCI state and the second TCI state or one or more PDSCH transmissions associated with the first TCI state and the second TCI state.

[0056] In an example embodiment, the second delay comprises determining the time from a predetermined part of the first occurring instance of the first SSB to a predetermined part of the first occurring instance of the second SSB as the sum of a Receive Timing Difference, RTD, and a predetermined first time period, i.e. the time required for panel switching or further internal processing at the receiving end or an estimate thereof, which is in an example embodiment at least in part based on an estimate of at least one capability at the receiving end. By determining the second delay in such a way, the network device knows that the delay in the TCI state switch is shorter, i.e. is not extended.

[0057] In an example embodiment, the network receives the predetermined first time period from the UE and can by having this information calculate when an additional delay is needed in the TCI state switching delay and hence, the network knows when it can start scheduling PDCCH / PDSCH for the UE.

[0058] In an example embodiment, the time from a predetermined part of the first occurring instance of the first SSB to a predetermined part of the first occurring instance of the second SSB is selected from the group of: the time from an end of the first SSB to the start of the second SSB; the time from an end of a Secondary Synchronization Signal, SSS, of the first SSB to a start of a Primary Synchronization Signal, PSS, of the second SSB the time from an end of a PSS of the first SSB to a start of a PSS of the second SSB; and the time from an end of a PSS of the first SSB to a start of a SSS of the second SSB.

[0059] In an example embodiment, for example if the network device does not know the RTD of the receiving UE, the RTD is a Maximum Receive Timing Difference, MRTD.

[0060] Fig 7 shows a flow chart of a method of an example embodiment. Fig. 7 shows a method of an example embodiment for a system of a UE and a network device. The method comprises701. Determining a second delay.702. Sending at least an indication indicating an activation of a first, Transmission Configuration Indicator, TCI state associated with a first Synchronization Signal Block, SSB, and a second TCI state associated with a second SSB, wherein the first occurring instance of the first SSB and the first occurring instance of the secondSSB are sent with the second delay.703. Receiving at least an indication indicating an activation of a first Transmission Configuration Indicator, TCI state associated with a first Synchronization Signal Block, SSB, and a second TCI state associated with a second SSB, wherein the first SSB is received from a first Transmission and Reception Point, TRP, and the second SSB is received from a second TRP.704. Determining a time difference between the first occurring instance of the first SSB and the first occurring instance of the second SSB.705. Synchronizing with the first occurring instance of the first SSB and after a first delay with an occurring instance of the second SSB, wherein the first delay is based at least in part on the determined time difference between the first occurring instance of the first SSB and the first occurring instance of the second SSB.706. Sending after a predetermined second time period at least one of one or more PDCCH transmissions associated with the first TCI state and the second TCI state or one or more PDSCH transmissions associated with the first TCI state and the second TCI state.

[0061] Fig. 8 shows a block diagram of an apparatus 800 according to an embodiment. The apparatus 800 is configured to function in an example embodiment as user equipment or network device.

[0062] The apparatus 800 comprises a memory 840 including a work memory 842 and a non-volatile memory 844 that contains computer program code 846 and data, such as preconfigured rules or configuration information. The apparatus 800 further comprises a processor 820 for controlling the operation of the apparatus 800 using the computer program code 846, a communication unit 810, such as a new radio capable of 5G cellular communications, for communicating with user equipment and / or cellular network. The communication unit 810 comprises, for example, a local area network (LAN) port; a wireless local area network (WLAN) unit; Bluetooth unit; cellular data communication unit; or satellite data communication unit. The processor 820 comprises, for example, any one or more of: a master control unit (MCU); a microprocessor; a digital signal processor (DSP); an application specific integrated circuit (ASIC); a field programmable gate array; and a microcontroller. The apparatus 800 further comprises a user interface 880, comprising, e.g., any one or more of a display, touch screen, button, microphone, speaker, fingerprint reader.

[0063] As used in this application, the term “circuitry” may refer to one or more or all of the following:(a) hardware-only circuit implementations (such as implementations in only analogue and / or digital circuitry) and;(b) combinations of hardware circuits and software, such as (as applicable):(i) a combination of analogue and / or digital hardware circuit(s) with software / firmware; and(ii) any portions of hardware processor(s) with software (including digital signal processor(s)), software, and memory(ies) that work together to cause an apparatus, such as a mobile phone or server, to perform various functions); and(c) hardware circuit(s) and I or processor(s), such as a microprocessor(s) or a portion of a microprocessor(s), that requires software (e.g., firmware) for operation, but the software may not be present when it is not needed for operation.

[0064] This definition of circuitry applies to all uses of this term in this application, including in any claims. As a further example, as used in this application, the term circuitry also covers an implementation of merely a hardware circuit or processor (or multiple processors) or portion of a hardware circuit or processor and its (or their) accompanying software and / or firmware. The term circuitry also covers, for example and if applicable to the particular claim element, a baseband integrated circuit or processor integrated circuit for a mobile device or a similar integrated circuit in server, a cellular network device, or other computing or network device.

[0065] As used herein, “at least one of the following: ” and “at least one of ” and similar wording, where the list of two or more elements are joined by “and” or “or”, mean at least any one of the elements, or at least any two or more of the elements, or at least all the elements.

[0066] Without in any way limiting the scope, interpretation, or application of the claims appearing below, a technical effect of one or more of the example embodiments disclosed herein is to enable the determination of whether the Synchronization Signal Blocks are adjacent or overlapping. Another technical effect of one or more of the example embodiments disclosed herein is to ensure that the network can operate with a shorter TCI state switch delay. Another technical effect of one or more of the example embodiments disclosed herein is that the network can avoid scheduling the SSBs from two TRPs so that the UE cannot synchronize with both of them on the first occasion during the TCI state switch.

[0067] Embodiments may be implemented in software, hardware, application logic or a combination of software, hardware, and application logic. The software, application logic and / or hardware may reside on a user equipment or network device or entity. If desired, part of the software, application logic and / or hardware may reside on a user equipment, and part of the software, application logic and / or hardware may reside on a network device or entity. In an example embodiment, the application logic, software, or an instruction set is maintained on any one of various conventional computer-readable media. In the context of this document, a“computer-readable medium” maybe any non-transitory media or means that can contain, store, communicate, propagate, or transport the instructions for use by or in connection with an instruction execution system, apparatus, or device, such as a computer, with one example of a computer described and depicted in Fig. 8. A computer-readable medium may comprise a computer-readable storage medium that may be any media or means that can contain or store the instructions for use by or in connection with an instruction execution system, apparatus, or device, such as a computer. The term non-transitory as used herein is a limitation of the medium itself (i.e., tangible, not a signal) as opposed to a limitation on data storage persistency (e.g., random access memory vs. read only memory).

[0068] If desired, the different functions discussed herein may be performed in a different order and / or concurrently with each other. Furthermore, if desired, one or more of the before-described functions may be optional or may be combined.

[0069] Although various aspects of the invention are set out in the independent claims, other aspects of the invention comprise other combinations of features from the described embodiments and / or the dependent claims with the features of the independent claims, and not solely the combinations explicitly set out in the claims.

[0070] It is also noted herein that while the foregoing describes example embodiments of the invention, these descriptions should not be viewed in a limiting sense. Rather, there are several variations and modifications which may be made without departing from the scope as defined in the appended claims.

Claims

CLAIMS1. An apparatus, comprising: at least one processor; and at least one memory storing instructions that, when executed by the at least one processor, cause the apparatus at least to: receive at least an indication indicating an activation of a first Transmission Configuration Indicator, TCI state associated with a first Synchronization Signal Block, SSB, and a second TCI state associated with a second SSB, wherein the first SSB is received from a first Transmission and Reception Point, TRP, and the second SSB is received from a second TRP; determine a time difference between the first occurring instance of the first SSB and the first occurring instance of the second SSB; and synchronize with the first occurring instance of the first SSB and after a first delay with an occurring instance of the second SSB, wherein the first delay is based at least in part on the determined time difference between the first occurring instance of the first SSB and the first occurring instance of the second SSB.

2. The apparatus of claim 1 , wherein the at least one processor is further configured to cause the apparatus after synchronizing with first occurring instance of the first SSB and with an occurring instance of second SSB with a first delay to receive at least one of one or more PDCCH transmissions associated with the first TCI state and the second TCI state or one or more PDSCH transmissions associated with the first TCI state and the second TCI state.

3. The apparatus of claim 1 or 2, wherein the determined time difference between the first occurring instance of the first SSB and the first occurring instance of the second SSB comprises the time from a predetermined part of the first SSB to a predetermined part of the second SSB.

4. The apparatus of any preceding claim 1 to 3, wherein the determined time difference between the first occurring instance of the first SSB and the first occurring instance of the second SSB comprises the time from an end of the first SSB to the start of the second SSB; or the time from an end of a Secondary Synchronization Signal, SSS, of the first SSB to a start of a Primary Synchronization Signal, PSS, of the second SSB; the time from an end of a PSS of the first SSB to a start of a PSS of the second SSB; or the time from an end of a PSS of the first SSB to a start of a SSS of the second SSB.

5. The apparatus of any preceding claim 1 to 4, wherein the at least one processor is further configured to cause the apparatus to determine the first delay based at least in part on the determined time difference between the first occurring instance of the first SSB and the first occurring instance of the second SSB, wherein determining the first delay comprises comparing the length of the determined time difference between the first SSB and the second SSB to a predetermined first time period.

6. The apparatus of claim 5, wherein the predetermined first time period comprises the time required for panel switching or further internal processing at the apparatus.

7. The apparatus of claim 6, wherein the predetermined first time period is determined at least in part based on at least one capability of the apparatus.

8. The apparatus of claim 7, wherein the processor is configured to cause the apparatus to send the value of the first time period.

9. The apparatus of any preceding claim 5 to 7, wherein the first delay is extended by a delay of a single SSB periodicity in case the length of the determined time difference between the first occurring instance of the first SSB and the first occurring instance of the second SSB is shorter than the predetermined first time period.

10. The apparatus of any preceding claim 5 to 8, wherein the first SSB and the second SSB are determined to be overlapping or adjacent in case the length of the determined time difference between the first occurring instance of the first SSB and the first occurring instance of the second SSB is shorter than the predetermined first time period.

11. The apparatus of any preceding claim 1 to 10, wherein the apparatus comprises or is comprised in a wireless device.

12. The apparatus of claim 11 , wherein the wireless device is a user equipment, UE.

13. An apparatus, comprising: at least one processor; and at least one memory storing instructions that, when executed by the at least one processor, cause the apparatus at least to: determine a second delay; send at least an indication indicating an activation of a first, Transmission Configuration Indicator, TCI state associated with a first Synchronization Signal Block,SSB, and a second TCI state associated with a second SSB, wherein the first occurring instance of the first SSB and the first occurring instance of the second SSB are sent with the second delay; and send after a predetermined second time period at least one of one or more PDCCH transmissions associated with the first TCI state and the second TCI state or one or more PDSCH transmissions associated with the first TCI state and the second TCI state.

14. The apparatus of claim 13, wherein determining the second delay comprises determining the time from a predetermined part of the first occurring instance of the first SSB to a predetermined part of the first occurring instance of the second SSB as the sum of a Receive Timing Difference, RTD, and the predetermined first time period.

15. The apparatus of 14, wherein the time from a predetermined part of the first occurring instance of the first SSB to a predetermined part of the first occurring instance of the secondSSB is selected from the group of: the time from an end of the first SSB to the start of the second SSB; the time from an end of a Secondary Synchronization Signal, SSS, of the first SSB to a start of a Primary Synchronization Signal, PSS, of the second SSB the time from an end of a PSS of the first SSB to a start of a PSS of the second SSB; and the time from an end of a PSS of the first SSB to a start of a SSS of the second SSB.

16. The apparatus of claim 14 or 15, wherein the Receive Timing Difference, RTD is a Maximum Receive Timing Difference, MRTD.

17. The apparatus of any preceding claim 14 to 16, wherein the predetermined first time period comprises an estimate of the time required for panel switching or further internal processing at the receiving end.

18. The apparatus of claim 17, wherein the predetermined first time period is determined at least in part based on an estimate of at least one capability at the receiving end, or based on a received value of the first time period.

19. The apparatus of claim 18, wherein determining the second delay comprises determining the time from a predetermined part of the first occurring instance of the first SSB to a predetermined part of the first occurring instance of the second SSB at least in part basedon at least one capability at the receiving end based on the received value of the first time period.

20. A method in an apparatus for a user equipment, comprising: receiving at least an indication indicating an activation of a first Transmission Configuration Indicator, TCI state associated with a first Synchronization Signal Block, SSB, and a second TCI state associated with a second SSB, wherein the first SSB is received from a first Transmission and Reception Point, TRP, and the second SSB is received from a second TRP; determining a time difference between the first occurring instance of the first SSB and the first occurring instance of the second SSB; and synchronizing with the first occurring instance of the first SSB and after a first delay with an occurring instance of the second SSB, wherein the first delay is based at least in part on the determined time difference between the first occurring instance of the first SSB and the first occurring instance of the second SSB.21 . A method in an apparatus for a network device, comprising: determining a second delay; sending at least an indication indicating an activation of a first, Transmission Configuration Indicator, TCI state associated with a first Synchronization Signal Block, SSB, and a second TCI state associated with a second SSB, wherein the first occurring instance of the first SSB and the first occurring instance of the second SSB are sent with the second delay; and sending after a predetermined second time period at least one of one or more PDCCH transmissions associated with the first TCI state and the second TCI state or one or more PDSCH transmissions associated with the first TCI state and the second TCI state.

22. An apparatus, comprising: means for receiving at least an indication indicating an activation of a first Transmission Configuration Indicator, TCI state associated with a first Synchronization Signal Block, SSB, and a second TCI state associated with a second SSB, wherein the first SSB is received from a first Transmission and Reception Point, TRP, and the second SSB is received from a second TRP; means for determining a time difference between the first occurring instance of the first SSB and the first occurring instance of the second SSB; andmeans for synchronizing with the first occurring instance of the first SSB and after a first delay with an occurring instance of the second SSB, wherein the first delay is based at least in part on the determined time difference between the first occurring instance of the first SSB and the first occurring instance of the second SSB.

23. An apparatus, comprising: means for determining a second delay; means for sending at least an indication indicating an activation of a first, Transmission Configuration Indicator, TCI state associated with a first Synchronization Signal Block, SSB, and a second TCI state associated with a second SSB, wherein the first occurring instance of the first SSB and the first occurring instance of the second SSB are sent with the second delay; and means for sending after a predetermined second time period at least one of one or more PDCCH transmissions associated with the first TCI state and the second TCI state or one or more PDSCH transmissions associated with the first TCI state and the second TCI state.

24. A computer program comprising instructions stored thereon for performing at least the method of any one of claims 20 or 21.

25. A non-transitory computer readable medium comprising program instructions stored thereon for performing at least the method of any one of claims 20 or 21.

26. A computer readable medium comprising program instructions stored thereon for performing at least the method of any one of claims 20 or 21.

27. A system comprising: at least one processor and at least one memory storing instructions that, when executed by the at least one processor, cause the system at least to: determine a second delay; send at least an indication indicating an activation of a first, Transmission Configuration Indicator, TCI state associated with a first Synchronization Signal Block, SSB, and a second TCI state associated with a second SSB, wherein the first occurring instance of the first SSB and the first occurring instance of the second SSB are sent with the second delay receive at least an indication indicating an activation of a first Transmission Configuration Indicator, TCI state associated with a first Synchronization Signal Block, 16SSB, and a second TCI state associated with a second SSB, wherein the first SSB is received from a first Transmission and Reception Point, TRP, and the second SSB is received from a second TRP; determine a time difference between the first occurring instance of the first SSB and the first occurring instance of the second SSB; and synchronize with the first occurring instance of the first SSB and after a first delay with an occurring instance of the second SSB, wherein the first delay is based at least in part on the determined time difference between the first occurring instance of the first SSB and the first occurring instance of the second SSB; and send after a predetermined second time period at least one of one or more PDCCH transmissions associated with the first TCI state and the second TCI state or one or more PDSCH transmissions associated with the first TCI state and the second TCI state.

28. A system comprising: means for determining a second delay; means for sending at least an indication indicating an activation of a first, Transmission Configuration Indicator, TCI state associated with a first Synchronization Signal Block, SSB, and a second TCI state associated with a second SSB, wherein the first occurring instance of the first SSB and the first occurring instance of the second SSB are sent with the second delay means for receiving at least an indication indicating an activation of a first Transmission Configuration Indicator, TCI state associated with a first Synchronization Signal Block, SSB, and a second TCI state associated with a second SSB, wherein the first SSB is received from a first Transmission and Reception Point, TRP, and the second SSB is received from a second TRP; means for determining a time difference between the first occurring instance of the first SSB and the first occurring instance of the second SSB; and means for synchronizing with the first occurring instance of the first SSB and after a first delay with an occurring instance of the second SSB, wherein the first delay is based at least in part on the determined time difference between the first occurring instance of the first SSB and the first occurring instance of the second SSB; and means for sending after a predetermined second time period at least one of one or more PDCCH transmissions associated with the first TCI state and the second TCI state or one or more PDSCH transmissions associated with the first TCI state and the second TCI state.

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