Patent Description:
In a typical wireless communication network, UEs, also known as wireless communication devices, mobile stations, stations (STA) and/or wireless devices, communicate via a Radio access Network (RAN) to one or more core networks (CN). The RAN covers a geographical area which is divided into service areas or cell areas, with each service area or cell area being served by a radio network node such as an access node e.g. a Wi-Fi access point or a radio base station (RBS), which in some radio access technologies (RAT) may also be called, for example, a NodeB, an evolved NodeB (eNodeB) and a gNodeB (gNB). The service area or cell area is a geographical area where radio coverage is provided by the radio network node. The radio network node operates on radio frequencies to communicate over an air interface with the UEs within range of the access node. The radio network node communicates over a downlink (DL) to the UE and the UE communicates over an uplink (UL) to the radio network node. The radio network node may be a distributed node comprising a remote radio unit and a separated baseband unit.

A Universal Mobile Telecommunications System (UMTS) is a third generation telecommunication network, which evolved from the second generation (<NUM>) Global System for Mobile Communications (GSM). The UMTS terrestrial radio access network (UTRAN) is essentially a RAN using wideband code division multiple access (WCDMA) and/or High-Speed Packet Access (HSPA) for communication with UEs. In a forum known as the Third Generation Partnership Project (3GPP), telecommunications suppliers propose and agree upon standards for present and future generation networks and UTRAN specifically, and investigate enhanced data rate and radio capacity. In some RANs, e.g. as in UMTS, several radio network nodes may be connected, e.g., by landlines or microwave, to a controller node, such as a radio network controller (RNC) or a base station controller (BSC), which supervises and coordinates various activities of the plural radio network nodes connected thereto. The RNCs are typically connected to one or more core networks.

Specifications for the Evolved Packet System (EPS) have been completed within the <NUM>rd Generation Partnership Project (3GPP) and this work continues in the coming 3GPP releases, such as <NUM> networks. The EPS comprises the Evolved Universal Terrestrial Radio Access Network (E-UTRAN), also known as the Long-Term Evolution (LTE) radio access network, and the Evolved Packet Core (EPC), also known as System Architecture Evolution (SAE) core network. E-UTRAN/LTE is a 3GPP radio access technology wherein the radio network nodes are directly connected to the EPC core network. As such, the Radio Access Network (RAN) of an EPS has an essentially "flat" architecture comprising radio network nodes connected directly to one or more core networks.

With the emerging <NUM> technologies also known as new radio (NR), the use of very many transmit- and receive-antenna elements makes it possible to utilize beamforming, such as transmit-side and receive-side beamforming. Transmit-side beamforming means that the transmitter can amplify the transmitted signals in a selected direction or directions, while suppressing the transmitted signals in other directions. Similarly, on the receive-side, a receiver can amplify signals from a selected direction or directions, while suppressing unwanted signals from other directions.

Beamforming allows the signal to be stronger for an individual connection. On the transmit-side this may be achieved by a concentration of the transmitted power in the desired direction(s), and on the receive-side this may be achieved by an increased receiver sensitivity in the desired direction(s). This beamforming enhances throughput and coverage of the connection. It also allows reducing the interference from unwanted signals, thereby enabling several simultaneous transmissions over multiple individual connections using the same resources in the time-frequency grid, so-called multi-user Multiple Input Multiple Output (MIMO).

<NUM> is the fifth generation of cellular technology and was introduced in Release <NUM> of the 3GPP standard. It is designed to increase speed, reduce latency, and improve flexibility of wireless services. The <NUM> system (5GS) includes both a new radio access network (NG-RAN) and a new core network (5GC).

SI is broadcast information in <NUM> - <NUM> RAN, which is transmitted periodically by the base station to the UE. SI comprises critical information for a UE to perform cell selection, cell access, cell reselection to other cells on the same frequency or to other frequencies or even to other RATs during mobility in radio resource control (RRC) Idle/inactive mode. System information provides all necessary details like System frame number, System bandwidth, public land mobile network (PLMN), cell selection and re-selection thresholds etc. to access a network. In addition, the system information may contain information needed for different services, such as Public Warning System, Device to Device, broadcast of positioning assistance data etc..

At high level in <NUM> New Radio the system information can be divided into three categories.

The MIB information is transmitted via broadcast channel (BCH) and physical broadcast channel (PBCH) channels while SIBs are transmitted via DL-shared channel (SCH) and physical downlink shared channel (PDSCH) channels.

Each OSI SIB has its own individual periodicity and is carried in SI messages. Within one SI message one or more SIBs can be contained if the periodicity, i.e., the rate at which the SIBs should be distributed, is the same and that the size allowed for the SI message is within the allowed limit. The maximum theoretical size for the SI message in NR stand-alone (SA) is <NUM> bits (<NUM> bytes) according to 3GPP, 3GPP TS <NUM> v16. <NUM>, but the actual size will depend on the selected numerology and cell bandwidth.

The type of SIBs for OSI can be divided into two categories:.

The scheduling information for each OSI SIB is carried in the SIB1, together with the periodicity and the mapping to SI messages. The SI messages are transmitted within periodically occurring time domain windows, referred to as SI-window. Each SI message is associated with an SI-window and the Sl-windows of different SI messages do not overlap. That is, within one SI-window only the corresponding SI message is transmitted. The length of the SI-window is common for all SI messages and is configurable. Within the SI-window, the corresponding SI message can be transmitted several times by Layer <NUM> to assure that devices on the cell edge are able to obtain the SI message. SIB1 also contains the SI-window length.

Dynamic Spectrum Sharing (DSS) is a new antenna technology that enables the parallel deployment of LTE and <NUM> using the same frequency spectrum. The technology determines the demand for <NUM> and LTE in real-time. The network then divides the available bandwidth independently and decides dynamically for which mobile communications standard it uses the available frequencies.

A <NUM> NR device needs to detect synchronization signal blocks (SSB) to access the network. To maintain synchronization in time and frequency, SSBs must be sent periodically by the network, with a gap defined to transmit the SSB on an already occupied frequency channel used by LTE. To allow this gap in a continuous LTE transmission, one solution is to use multimedia broadcast single frequency network (MBSFN) subframes. To get a robust implementation of the distribution of the <NUM> NR System information the SI messages are also confined to the MBSFN subframes, but different subframes compared to the ones used for SSB.

To minimize the impact on LTE performance, typically only a few out of the possible <NUM> subframes are configured to be MBSFN subframes. The applied configuration is broadcast by the LTE with system information block type <NUM> (SIB2). A standard LTE terminal would read in the MBSFN configuration from SIB2 and ignore the subframes configured for broadcast.

DSS additionally enables the use of non-MBSFN subframes for NR on a need basis, typically used for the user data. DSS was included already in Rel-<NUM> and further enhanced in Rel-<NUM>.

In TS <NUM>, several positioning SIBs have been defined. Broadcast would be essential for scaling reasons when massive UE request positioning SIBs. This additionally put constraints on the NW side to dimension the NW to support broadcast. A list of posSIBs is tabulated below [TS <NUM> v <NUM>.

There is a limit on the amount of SI messages that can be distributed for a certain deployment. It will depend on the numerology and the following formula needs to be fulfilled: <MAT>.

3GPP ranges see <NUM> "Radio Resource Control (RRC) protocol specification", V16. <NUM>: SIB Periodicity = <NUM>x × <NUM> where <NUM> ≤ x ≤ <NUM> ,
SI-window length = <NUM>y × <NUM> × slot length, where <NUM> ≤ y ≤ <NUM> and slot length = <NUM>ms for LB, <NUM> for MB.

The SI-window length needs to assure a robust distribution of the SIBs by repetition on layer one (L1), i.e., enough number of slots inside the SI-window needs to be available for the L1 repetition. The number of L1 repetitions required relates to the actual size of the SI messages and the desired robustness is implementation specific as well as how many slots that are allowed for OSI.

The size of an SI message is limited to max <NUM> bits in NR, see <NUM> "Radio Resource Control (RRC) protocol specification", V16. <NUM>, and depends on the cell bandwidth. A smaller SI message size will require less L1 repetitions, but the minimum required window size needs to fit the SIB with the largest size plus the SI message header.

With DSS the slots for the distribution of OSI is very limited when OSI is confined to MBSFN subframes and the SI-window length needs to be long to allow for L1 repetition. As other control information, e.g., SSB, needs to be confined to the MBSFN slots, it is not desired to counter for more than <NUM> slot for OSI every <NUM>, providing a total allocation of e.g. <NUM> MBSFN subframes for NR. Consequently, the SI-window Length needs to be at least <NUM>, to allow for one re-transmission, and the shortest periodicity allowing more than <NUM> SI messages would then need to be <NUM>. Typically, to provide good enough robustness the SI-window would need to be at least <NUM> together with DSS, and the minimum periodicity for more than <NUM> SI messages needs to be as high as <NUM>.

NR should allow contiguous scheduling of up to <NUM> Sls, max number of SI supported. If there is any collision as shown, diagonal stripes, in <FIG> the handling of such collision avoidance is not provided.

Considering: SI1 has periodicity of <NUM> and SI window of <NUM> has been configured and there are <NUM> Sls in total.

The current specification has a partial solution. The field offsetToSI-Used, TS <NUM> v16. <NUM>, in NR was imported from LTE. This provides an offset of hardcoded <NUM> + any offsets based upon number of Sls configured with <NUM> periodicity SI. The main purpose with the offset is to avoid any collision that may happen when <NUM> SI, NR legacy SI, periodicity may reoccur at a start slot of positioning SI.

The procedure of the offset is written based upon typical LTE configuration where the shortest periodicity is <NUM>. Besides, in many operators network (NW) the SI-Window configured in LTE was <NUM>. Hence, it was assumed that first <NUM> radio frames (rf) can be kept for LTE SI and after <NUM> + the reoccurrence of <NUM> Sls; then the positioning SI can start.

When Dynamic shared spectrum feature is used, a typical SI-Window length would be between <NUM> -<NUM>, depending on the amount of MBSFN subframes available for System Information. Also, in deployments without DSS a typical shortest periodicity in NR is set to <NUM>. With these sorts of configurations and deployments, the current offsetToSI-Used based upon <NUM> hardcoded offset will fail.

Further, to illustrate the problem, a simplified table is shown below where at the start of system frame number (SFN)#<NUM> or at the start of SI scheduling; the radio frames and slots are occupied. However, there are also regions which are un-occupied and can be potentially exploited.

An object of embodiments herein is to provide a mechanism that improves communication during a handover in the wireless communication network.

Relevant prior art can also be found in:.

Embodiments herein are described in the context of <NUM>/NR but the same concept can also be applied to other wireless communication system such as <NUM>/LTE. Embodiments herein may be described within the context of 3GPP NR radio technology (<NPL>)), e.g., using gNB as the radio network node. It is understood, that the problems and solutions described herein are equally applicable to wireless access networks and user-equipments (UEs) implementing other access technologies and standards. NR is used as an example technology where embodiments are suitable, and using NR in the description therefore is particularly useful for understanding the problem and solutions solving the problem. In particular, embodiments are applicable also to 3GPP LTE, or 3GPP LTE and NR integration, also denoted as non-standalone NR.

Embodiments herein relate to wireless communication networks in general. <FIG> is a schematic overview depicting a wireless communication network <NUM>. The wireless communication network <NUM> comprises, e.g., one or more RANs and one or more CNs. The wireless communication network <NUM> may use one or a number of different technologies, such as Wi-Fi, Long Term Evolution (LTE), LTE-Advanced, NR, Wideband Code Division Multiple Access (WCDMA), Global System for Mobile communications/enhanced Data rate for GSM Evolution (GSM/EDGE), Worldwide Interoperability for Microwave Access (WiMax), or Ultra Mobile Broadband (UMB), just to mention a few possible implementations. Embodiments herein relate to recent technology trends that are of particular interest in <NUM> systems, however, embodiments are also applicable in further development of the existing communication systems such as, e.g., a WCDMA or a LTE system.

In the wireless communication network <NUM>, UEs, e.g., a UE <NUM> such as a mobile station, a non-access point (non-AP) station (STA), a STA, a wireless device and/or a wireless terminal, communicate via one or more Access Networks (AN), e.g., RAN, to one or more core networks (CN). It should be understood by the skilled in the art that "UE" is a non-limiting term which means any terminal, wireless communication terminal, wireless device, Machine Type Communication (MTC) device, Device to Device (D2D) terminal, internet of things (IoT) operable device, or node e.g. smart phone, laptop, mobile phone, sensor, relay, mobile tablets or even a small base station capable of communicating using radio communication with a network node within an area served by the network node.

The communication network <NUM> comprises a radio network node <NUM> providing, e.g., radio coverage over a geographical area, a first service area <NUM>, i.e., a first cell, of a radio access technology (RAT), such as NR, LTE, Wi-Fi, WiMAX or similar. The radio network node <NUM> may be a transmission and reception point, a computational server, a base station e.g. a network node such as a satellite, a Wireless Local Area Network (WLAN) access point or an Access Point Station (AP STA), an access node, an access controller, a radio base station such as a NodeB, an evolved Node B (eNB, eNodeB), a gNodeB (gNB), a base transceiver station, a baseband unit, an Access Point Base Station, a base station router, a transmission arrangement of a radio base station, a stand-alone access point or any other network unit or node depending e.g. on the radio access technology and terminology used. The radio network node <NUM> may alternatively or additionally be a controller node or a packet processing node or similar. The radio network node <NUM> may be referred to as source node, source access node or a serving network node wherein the first service area <NUM> may be referred to as a serving cell, source cell or primary cell, and the radio network node communicates with the UE <NUM> in form of DL transmissions to the UE <NUM> and UL transmissions from the UE <NUM>. The radio network node may be a distributed node comprising a baseband unit and one or more remote radio units.

It should be noted that a service area may be denoted as cell, beam, beam group or similar to define an area of radio coverage.

According to embodiments herein one or more SI messages are scheduled using a first or a second list of scheduling information. The UE <NUM> determines, if the SI message is scheduled using the first list of scheduling information, the start position of the SI window based on a location of the SI message in the first list of scheduling information. If the SI message is scheduled using the second list of scheduling information, the UE <NUM> determines the start position of the SI window by taking a received input parameter into account, wherein the received input parameter is indicating the start position of the SI window used for acquiring the SI message. The UE <NUM> may thus acquire a system information message, being configured by the second list of scheduling information, taking the received, from the radio network node <NUM>, input parameter into account.

The method actions performed by the UE <NUM> for determining the start position of the SI window to acquire the SI message in the wireless communication network <NUM> according to embodiments herein will now be described with reference to a flowchart depicted in <FIG>. The actions do not have to be taken in the order stated below, but may be taken in any suitable order. Actions performed in some embodiments are marked with dashed boxes. One or more SI messages are scheduled using the first or the second list of scheduling information.

Action <NUM>. The UE <NUM> may receive, from the network, configuration indicating if the SI message is scheduled using the first or the second list of scheduling information, and/or the input parameter indicating the start position of the SI window used for acquiring the SI message, thereby allowing the SI window to be offset.

Action <NUM>. The UE <NUM> determines, if the SI message is scheduled using the first list of scheduling information, the start position of the SI window based on a location of the SI message in the first list of scheduling information.

Action <NUM>. The UE <NUM> determines, if the SI message is scheduled using the second list of scheduling information, the start position of the SI window by taking the received input parameter into account, wherein the received input parameter is indicating the start position of the SI window used for acquiring the SI message. The received input parameter may be a value configured at the radio network node. In an example, the start position is determined, in case the SI message is scheduled using the second list of scheduling information, based on an integer value, which integer value is based on said received input parameter and window length of the SI message. The integer value may be calculated by taking the received input parameter minus <NUM> and multiplying it with a value representing the window length of the SI window. The integer value may designate where in the second list the SI is scheduled to start. Thus, the integer value x = (input parameter - <NUM>) × w, where w is the si-WindowLength. Furthermore, the SI-window starts at the slot #a, where a = x mod N, in the radio frame for which SFN mod T = FLOOR(x/N), where T is the si-Periodicity of the concerned SI message and N is the number of slots in a radio frame.

The received input parameter may be indicated in an information element (IE), in which presence in said IE indicates a start position of the SI window. Alternatively, the received input parameter may be indicated in a field in a message in which presence of said field indicates a start position of the SI window.

The method actions performed by the radio network node <NUM> for handling communication in the wireless communication network <NUM> according to embodiments herein will now be described with reference to a flowchart depicted in <FIG>. The actions do not have to be taken in the order stated below, but may be taken in any suitable order. Actions performed in some embodiments are marked with dashed boxes.

Action <NUM>. The radio network node <NUM> may determine the start position for a respective SI message out of a number of SI messages that are to be scheduled in a cell of the radio network node.

Action <NUM>. The radio network node <NUM> determines whether one or more SI messages have a unique start position or not. For example, the radio network node <NUM> may determine whether the one or more SI messages have a unique start position or not by determining whether or not a number of SI messages that are to be scheduled have a respective start position, where there is a conflict with another SI message or/and resources are not evenly occupied in time frequency domain.

Action <NUM>. The radio network node <NUM> determines, with the proviso that the one or more SI messages do not have a unique start position, an updated start position for the one or more SI messages. Thus, with the proviso that one or more SI messages have a conflicting position with another SI message, i.e., that the one or more SI messages do not have a unique start position, the radio network node <NUM> determines additional updated start positions for the one or more SI messages.

Action <NUM>. The radio network node <NUM> further transmits the input parameter to the UE <NUM> indicating the start position of the SI window used for acquiring the one or more SI messages.

The radio network node may configure the UE <NUM> with the input parameter, and that one or more SI messages are scheduled in the first and the second list of scheduling information.

The radio network node <NUM> may for example, configure the UE that SI messages are scheduled in the first and the second list of scheduling information and may indicate with the input parameter indicating the start position of the SI window used for acquiring the SI message, thereby allowing the SI window to be offset.

In some embodiments, the radio network node <NUM> may schedule SI according to two formulas, also referred to as procedures, for determining the start position of SI windows for SI messages.

There are thus two scheduling procedures for SI windows for SI messages:
A first procedure which is one which is described in current 3GPP TS <NUM> v16. <NUM> section <NUM>. <NUM>, it is shown here below. This procedure determines the position of a system information message by using a number n which is determined by the order of the SI-message in the first list of scheduling information also referred to as scheduling info list or schedulinglnfoList. The number n is then used to determine a parameter x which is used to determine the point in time when the SI window for this SI message starts.

When acquiring an SI message, according to the first procedure, the UE <NUM> may:.

As can be seen, the starting time of the SI-window according to the first procedure depends on the location of the SI message in the first list of scheduling information. This results in that all SI messages has a pre-defined starting position, i.e., pre-defined in the sense that the starting position is defined by the location of the SI message in the first list.

This becomes limiting as illustrated by the <FIG>. In the <FIG> it is shown bars on <NUM> different levels. Time is defined on the x-axis. Each level (y-axis) corresponds to a particular SI message and the bars on a level N indicates the SI windows for the SI message N. We can for example see that SI message <NUM> has an SI window starting at time <NUM> since there is a bar on level <NUM> starting at time <NUM>. The <FIG> illustrates a limitation of the above procedure. It is shown that the SI window for SI message <NUM> (i.e. level <NUM>) collides with SI message <NUM>'s window since they occur at the same time.

The second procedure is, according to embodiments herein, a procedure wherein the UE <NUM> takes an indication e.g. an input parameter denoted e.g. si-WindowOffset or si-WindowStart-r16, into account when determining the parameter x according to the formula below.

The second procedure thus allows the network to offset the SI window for an SI message, and this can be done independently of e.g. the location of an SI message in any list. <FIG> shows the same number of SI messages as was shown in the <FIG>, however, the second procedure has been applied for SI message <NUM>. As can be seen the SI message <NUM> has been offset in time so it does not collide with any other SI message.

Selection of procedure for an SI message.

Whether the first or the second procedure is applied for an SI-message may be determined based on if the SI message is scheduled using the first or the second list of scheduling information. The first list may be denoted as schedulingInfoList and the second list may be denoted as schedulinglnfoList2 or schedulingInfoListExt. This may be implemented as follows. In the following it can be seen that there is an if-statement which determines if the SI message is scheduled in the schedulingInfoList or scheduled in the schedulinglnfoList2. If a particular SI message is configured in the schedulingInfoList (i.e. without a trailing <NUM>) the first procedure is used for determining the time of the corresponding SI window. While if the SI message is configured in schedulinglnfoList2, which can also be termed as schedulingInfoListExt, the UE <NUM> applies the second procedure.

When acquiring an SI message, the UE shall:.

Note in the above example implementation of embodiments, there is an if-elseif statement which is used to determine if the schedulinglnfoList2(schedulinglnfoListExt) is applicable. However, it would be possible to have a simple if-else statement, like in the below:
When acquiring an SI message, the UE shall:.

The maximum value of the input parameter, here denoted si-WindowOffset, can be deduced based upon the NR-numerology that has been used. Considering that for subcarrier spacing (SCS) of <NUM>, accommodating <NUM> slots per radio frame, the minimum SI-Window length that can be configured is <NUM> slots, and the maximum SI periodicity is <NUM> radio frames. Hence, an input parameter in terms of SI-window would be <NUM> (<NUM>*<NUM>/<NUM>); i.e., there can be at max <NUM> SI-Window position.

This would require <NUM> bits. There is possibility to compress by giving choice between the commonly configured SI-Window length and subcarrier spacing (SCS). For example, for <NUM> and SI-WindowLength of <NUM> slots; the input parameter can be <NUM>, which will be indicated with <NUM> bits.

In terms of ASN. <NUM> relating to the input parameter being exemplified as a posSI-WindowOffset, the choice of the input parameter may be as below where for different SCS we can have different values
<IMG>.

Alternatively, using combination of SCS and two different SI-Window length slots, such as a first SI-window length of <NUM> slots and one smaller of <NUM> slots, the input parameter may be defined in:
<IMG>.

Thus, the input parameter may be based on SCS.

An alternate option to compress is that since there are maximum <NUM> Sls; the offset is designated in terms of where in the list the SI appears.

In order to avoid any repetition of reoccurrence of an SI in a designated start slot; the start position of SI is shifted. The number of shifts depends upon how many SI reoccurs periodically.

<FIG> shows an example. Considering <NUM> Sls kept in a contiguous way for scheduling. But S1 needs to reoccur before S9 is scheduled. Then the position of S9 will be taken by S1 and S9 position would be shifted.

As there are <NUM> Sls; one can consider a queue/list of <NUM> items; however, since there will be need of shift; the number of shifts or manipulation/change of start position; thus the array can be considered to be a maximum of <NUM>; hence an Integer (<NUM>. <NUM>) value can be provided to designate where in the array/list the SI is scheduled to start.

Changes to the relevant standard may be needed for how non-positioning Sls and positioning Sis are scheduled.

In terms of procedure text; the text below is shown for both non-positioning and positioning Sls. For the positioning Sls the input parameter may be termed as posSI-WindowOffset.

For positioning SI, separate second list also denoted as posSchedulingInfoList exist where the new formula can be used. For the non-positioning Sls in order not to impact the legacy Rel-<NUM> Sls a separate second list of scheduling information can be created which can be termed.

The required change is shown as underlined and bold in the following sections (baseline text from TS <NUM> section <NUM>.

The IE SI-SchedulingInfo contains information needed for acquisition of SI messages.

<FIG> is a combined signalling scheme and flowchart according to some embodiments herein for SI provision in the wireless communication network.

Action <NUM>. The radio network node <NUM> determines whether or not a required number of SI messages that is to be scheduled have a respective start position where, in said respective start position, there is a conflict with another SI message or/and resources are not evenly occupied in time frequency domain. Thus, the radio network node <NUM> determines whether the one or more SI messages have a unique start position.

Action <NUM>. The radio network node <NUM> may select or determine (or redetermine) an updated start position for the SI messages that have a conflict with another SI message and/or which resources are not evenly occupied in time frequency domain. Thus, with the proviso that one or more SI messages have a conflicting position with another SI message, the radio network node <NUM> determines additional one or more start positions for the one or more SI messages.

Action <NUM>. The radio network node <NUM> further transmits an indication, also denoted as input parameter, to a UE indicating the determined updated start positions for the SI messages. The radio network node <NUM> may for example, configure the UE <NUM> that SI messages are scheduled in the first and the second list of scheduling information and may indicate the input parameter such as an offset in time and/or slots/frames. Hence, the indication or the input parameter may comprise an offset and may be related to SI messages of the first and/or the second list. The input parameter may be denoted as a si-WindowOffset and indicated in an IE or a field in a message. This field, if present may indicate the configured offset relative another SI window in number of SI-Windowlength slots to determine the start slot of the SI message in the second list; for e.g. Value <NUM> may represent at SI-Window slot1, value <NUM> at SI-Window slot <NUM> and so on.

Action <NUM>. The radio network node <NUM> may then transmit (broadcast) SI information in the cell. Action <NUM> may be a part of the Action <NUM>.

Action <NUM>. The UE <NUM> may acquire a first SI message of a first set of SI messages based upon an ascending order of the first list of scheduling information whereas the UE <NUM> may obtain a second SI message of a second set of SI messages based on the signaled input parameter and applicable per SI. Thus, the UE <NUM> may use a first SI window to acquire a first SI message based on the first list of scheduling information and may use a second SI window to acquire a second SI message based on the received input parameter or indication indicating an offset in time and/or slots/frames. The start position of the second window is based on the indication, i.e., input parameter.

The method actions performed by the UE <NUM> for handling communication in the wireless communication network <NUM> according to some example embodiments herein will now be described with reference to a flowchart depicted in <FIG>. The actions do not have to be taken in the order stated below, but may be taken in any suitable order. Actions performed in some embodiments are marked with dashed boxes.

Action <NUM>. The UE <NUM> may receive the indication from the radio network node <NUM> indicating the determined updated start positions for the one or more SI messages. The UE <NUM> may obtain configuration indicating that SI messages are scheduled in one or more lists of scheduling information e.g. the first and/or the second list of scheduling information and may indicate the offset in time and/or slots/frames. Hence, the indication may comprise the offset and may be related to SI messages of the one or more lists. The respective list may be a SI scheduling information list or a position SI scheduling information list. The offset may be denoted as a SI-WindowOffset and indicated in the IE or the field in the message. This field, if present may indicate the configured offset in number of slots to determine the start slot of the SI message in the second list of scheduling information. The UE <NUM> may thus receive configuration data from the radio network node comprising the indication. The indication indicating the offset may also be termed as si-WindowStart-r16; wherein si-WindowStart-r16 Identifies the start of the SI-windows carrying this SI-message.

Action <NUM>. The UE <NUM> may acquire a SI message, being configured by the second list of scheduling information, taking the received indication into account, wherein the indication is an indication of an offset of a start position of the SI window for acquiring the SI message. The UE <NUM> may use the indication to determine a start position for a SI window used for acquiring SI messages. The UE <NUM> may acquire a first SI message of a first set of SI messages based upon an ascending order of the first list of scheduling information whereas the UE <NUM> may obtain a second SI message of a second set of SI messages based on the signaled indication and applicable per SI. Thus, the UE <NUM> may use a first SI window to acquire a first SI message based on the first list of scheduling information and may use a second SI window to acquire a second SI message based on an offset in time and/or slots/frames. The start position of the second window may thus be based on the indication.

The method actions performed by the radio network node <NUM> for handling communication in the wireless communication network <NUM> according to some example embodiments herein will now be described with reference to a flowchart depicted in <FIG>. The actions do not have to be taken in the order stated below but may be taken in any suitable order. Actions performed in some embodiments are marked with dashed boxes.

Action <NUM>. The radio network node <NUM> may determine or evaluate number of SI messages that is to be scheduled in the cell and may determine start positions for respective SI message.

Action <NUM>. The radio network node <NUM> determines whether or not the number of SI messages that is to be scheduled have a respective start position where in said respective start position there is a conflict with another SI message or/and resources are not evenly occupied in time frequency domain. Thus, the radio network node <NUM> determines whether the one or more SI messages have a unique start position or not.

Action <NUM>. The radio network node <NUM> selects or determines an updated start position for the one or more SI messages that have a conflict with another SI message and/or which resources are not evenly occupied in time frequency domain. Thus, with the proviso that one or more SI messages have a conflicting position with another SI message, i.e., that the one or more SI messages do not have a unique start position, the radio network node <NUM> determines additional updated start positions for the one or more SI messages.

Action <NUM>. The radio network node <NUM> further transmits an indication to the UE <NUM>, i.e., broadcasts, indicating the determined updated start positions for the one or more SI messages. The radio network node <NUM> may for example, configure the UE <NUM> that SI messages are scheduled according to the first and the second list of scheduling information and may indicate with the indication an offset in time and/or slots/frames. Hence, the indication may comprise an offset and may be related to SI messages of the first and/or the second list. The indication indicating the offset may be denoted as a si-WindowOffset and indicated in the IE or the field in the message. This field, if present, may indicate the configured offset in number of slots to determine the start slot of the SI message in the list. The indication indicating the offset may also be termed as si-WindowStart-r16; wherein si-WindowStart-r16 Identifies the start of the SI-windows carrying this SI-message.

<FIG> is a schematic overview depicting a method, according to some embodiments herein, performed by the radio network node <NUM>.

Action <NUM>. The radio network node <NUM> may evaluate number of SI messages that needs to be scheduled in the cell and may determine a start occasion, e.g., a SFN and start slot, for each SI.

Action <NUM>. The radio network node <NUM> may determine if the required number of SI messages that needs to be scheduled have a unique start position; i.e., there is no risk/conflict of any other SI message or/and the resources are evenly occupied in time frequency domain.

Action <NUM>. With the proviso that the one or more SI messages have a conflicting start position, the radio network node <NUM> may evaluate number of Sls whose start position needs to be determined.

Action <NUM>. The radio network node <NUM> may further compute (or select) a new start occasion for the concerned Sis. Thus, the radio network node <NUM> selects additional start positions for the one or more SI messages with start positions conflicting with other SI messages.

Action <NUM>. The radio network node <NUM> may then provide signalling via RRC broadcast to UEs of the SI start position. For example, transmit indication of the offset for the second set of SI messages. The indication indicating the offset may be denoted as the input parameter or a si-WindowOffset and indicated in an IE or a field in a message. This field, if present, may indicate the configured offset in number of slots to determine the start slot of the SI message in the list.

<FIG> is a block diagram depicting the UE <NUM> for determining the start position of the SI window to acquire the SI message in the wireless communication network <NUM> according to embodiments herein. One or more SI messages are scheduled using the first or the second list of scheduling information. The UE <NUM> may be for handling communication, e.g., handling SI, in the wireless communication network <NUM>.

The UE <NUM> may comprise processing circuitry <NUM>, e.g., one or more processors, configured to perform the methods herein.

The UE <NUM> may comprise a receiving unit <NUM>, e.g., a receiver or a transceiver. The UE <NUM>, the processing circuitry <NUM> and/or the receiving unit <NUM> is configured to, if the SI message is scheduled using the first list of scheduling information, determine the start position of the SI window based on the location of the SI message in the first list of scheduling information. The UE <NUM>, the processing circuitry <NUM> and/or the receiving unit <NUM> is configured to, if the SI message is scheduled using the second list of scheduling information, determine the start position of the SI window by taking the received input parameter into account, wherein the received input parameter is indicating the start position of the SI window used for acquiring the SI message. The UE <NUM>, the processing circuitry <NUM> and/or the receiving unit <NUM> may be configured to receive, from the network, configuration indicating if the SI message is scheduled using the first or the second list of scheduling information, and/or the input parameter indicating the start position of the SI window used for acquiring the SI message, thereby allowing the SI window to be offset. The received input parameter may be a value configured at the radio network node <NUM>. The UE <NUM>, the processing circuitry <NUM> and/or the receiving unit <NUM> may be configured to determine the start position, in case the SI message is scheduled using the second list of scheduling information, based on the integer value, which integer value is based on said received input parameter and the window length of the SI message. The UE <NUM>, the processing circuitry <NUM> and/or the receiving unit <NUM> may be configured to calculate the integer value by taking the received input parameter minus <NUM> and multiplying it with a value representing the window length of the SI window. The received input parameter may be indicated in the IE, in which presence in said IE indicates the start position of the SI window. The received input parameter may be indicated in the field in the message in which presence of said field indicates the start position of the SI window.

The UE <NUM>, the processing circuitry <NUM> and/or the receiving unit <NUM> may be configured to receive the indication from the radio network node <NUM> indicating the determined updated start positions for the one or more SI messages. The UE <NUM>, the processing circuitry <NUM> and/or the receiving unit <NUM> may be configured to obtain configuration indicating that SI messages are scheduled in one or more lists of scheduling information, e.g., the first and/or the second list of scheduling information and may indicate the offset in time and/or slots/frames. Hence, the indication may comprise the offset and may be related to SI messages of the one or more lists. The list may be a SI scheduling information list or a position SI scheduling information list. The offset may be denoted as a si-WindowOffset and indicated in the IE or the field in the message. This field, if present, may indicate the configured offset in number of slots to determine the start slot of the SI message in the second list of scheduling information. The UE <NUM>, the processing circuitry <NUM> and/or the receiving unit <NUM> may be configured to receive configuration data from the radio network node comprising the indication.

The UE <NUM>, the processing circuitry <NUM> and/or the receiving unit <NUM> is configured to acquire a SI message, being configured by a list of scheduling information, taking the received indication into account, wherein the indication is an indication of an offset of a start position for the SI message. The UE <NUM>, the processing circuitry <NUM> and/or the receiving unit <NUM> may be configured to use the indication to determine a start position for a SI window used for acquiring SI messages. The UE <NUM>, the processing circuitry <NUM> and/or the receiving unit <NUM> may be configured to acquire a first SI message of a first set of SI messages based upon an ascending order of a first list of scheduling information whereas the UE <NUM> may obtain a second SI message of a second set of SI messages based on the signaled indication and applicable per SI. Thus, the UE <NUM>, the processing circuitry <NUM> and/or the receiving unit <NUM> may be configured to use the first SI window to acquire the first SI message based on the first list of scheduling information and to use the second SI window to acquire the second SI message based on an offset in time and/or slots/frames. The start position of the second window may thus be based on the indication.

The UE <NUM> further comprises a memory <NUM>. The memory comprises one or more units to be used to store data on, such as indications, SI messages, SI configuration, strengths or qualities, grants, indications, reconfiguration, configuration, values, scheduling information, timers, applications to perform the methods disclosed herein when being executed, and similar. The UE <NUM> comprises a communication interface <NUM> comprising transmitter, receiver, transceiver and/or one or more antennas. Thus, it is herein provided the UE for handling communication in a wireless communications network, wherein the UE comprises processing circuitry and a memory, said memory comprising instructions executable by said processing circuitry whereby said UE is operative to perform any of the methods herein.

The methods according to the embodiments described herein for the UE <NUM> are respectively implemented by means of e.g. a computer program product <NUM> or a computer program product, comprising instructions, i.e., software code portions, which, when executed on at least one processor, cause the at least one processor to carry out the actions described herein, as performed by the UE <NUM>. The computer program product <NUM> may be stored on a computer-readable storage medium <NUM>, e.g. a universal serial bus (USB) stick, a disc or similar. The computer-readable storage medium <NUM>, having stored thereon the computer program product, may comprise the instructions which, when executed on at least one processor, cause the at least one processor to carry out the actions described herein, as performed by the UE <NUM>. In some embodiments, the computer-readable storage medium may be a non-transitory or transitory computer-readable storage medium.

<FIG> is a block diagram depicting the radio network node <NUM>, in two embodiments, for handling communication, e.g., handling SI, in the wireless communication network <NUM> according to embodiments herein.

The radio network node <NUM> may comprise processing circuitry <NUM>, e.g. one or more processors, configured to perform the methods herein.

The radio network node <NUM> may comprise a determining unit <NUM>. The radio network node <NUM>, the processing circuitry <NUM> and/or the determining unit <NUM> may be configured to determine or evaluate number of SI messages that is to be scheduled in the cell and may determine start positions for respective SI message. The radio network node <NUM>, the processing circuitry <NUM> and/or the determining unit <NUM> is configured to determine whether or not the number of SI messages that is to be scheduled have a respective start position where in said respective start position there is a conflict with another SI message or/and resources are not evenly occupied in time frequency domain. Thus, the radio network node <NUM>, the processing circuitry <NUM> and/or the determining unit <NUM> is configured to determine whether the one or more SI messages have a unique start position or not. For example, the radio network node <NUM>, the processing circuitry <NUM> and/or the selecting unit <NUM> may be configured to determine whether or not a number of SI messages that are to be scheduled have a respective start position where there is a conflict with another SI message or/and resources are not evenly occupied in time frequency domain.

The radio network node <NUM> may comprise a selecting unit <NUM>. The radio network node <NUM>, the processing circuitry <NUM> and/or the selecting unit <NUM> may be configured to select or determine an updated start position for the one or more SI messages that have a conflict with another SI message and/or which resources are not evenly occupied in time frequency domain. Thus, with the proviso that one or more SI messages have a conflicting position with another SI message i.e. that the one or more SI messages do not have a unique start position, the radio network node <NUM>, the processing circuitry <NUM> and/or the selecting unit <NUM> is configured to determine the updated, or additional, start position for the one or more SI messages. For example, the radio network node <NUM>, the processing circuitry <NUM> and/or the selecting unit <NUM> may be configured to determine the start position for the respective SI message out of the number of SI messages that are to be scheduled in a cell of the radio network node <NUM>.

The radio network node <NUM> may comprise a transmitting unit <NUM>, e.g., a transmitter or a transceiver. The radio network node <NUM>, the processing circuitry <NUM> and/or the transmitting unit <NUM> is configured to transmit the input parameter to the UE <NUM>, i.e., broadcast the indication or input parameter, wherein the input parameter indicates the start position of the SI window used for acquiring the one or more SI messages, and thus may indicate the determined updated start positions for the one or more SI messages. The radio network node <NUM>, the processing circuitry <NUM> and/or the transmitting unit <NUM> may be configured using the first and the second list of scheduling information, and to configure the UE with the input parameter, and that one or more SI messages are scheduled The radio network node <NUM>, the processing circuitry <NUM> and/or the transmitting unit <NUM> may be configured to configure the UE that SI messages are scheduled in the first and the second list of scheduling information and may indicate with the input parameter an offset in time and/or slots/frames of the SI-window. Hence, the indication, i.e., the input parameter, may comprise an offset and may be related to SI messages of the first and/or the second list. The transmitted input parameter may be indicated in an IE, in which presence in said IE indicates the start position of the SI window. The transmitted input parameter may be indicated in the field in the message in which presence of said field indicates the start position of the SI window. The offset may be denoted as a si-WindowOffset and indicated in an IE or a field in a message. This field, if present, may indicate the configured offset in number of slots to determine the start slot of the SI message in the list.

The radio network node <NUM> further comprises a memory <NUM>. The memory comprises one or more units to be used to store data on, such as indications, input parameters, strengths or qualities, grants, messages, execution conditions, user data, reconfiguration, configurations, scheduling information, timers, applications to perform the methods disclosed herein when being executed, and similar. The radio network node <NUM> comprises a communication interface <NUM> comprising transmitter, receiver, transceiver and/or one or more antennas. Thus, it is herein provided the radio network node for handling communication in a wireless communications network, wherein the radio network node comprises processing circuitry and a memory, said memory comprising instructions executable by said processing circuitry whereby said radio network node is operative to perform any of the methods herein.

The methods according to the embodiments described herein for the radio network node <NUM> are respectively implemented by means of, e.g., a computer program product <NUM> or a computer program product, comprising instructions, i.e., software code portions, which, when executed on at least one processor, cause the at least one processor to carry out the actions described herein, as performed by the radio network node <NUM>. The computer program product <NUM> may be stored on a computer-readable storage medium <NUM>, e.g., a universal serial bus (USB) stick, a disc or similar. The computer-readable storage medium <NUM>, having stored thereon the computer program product, may comprise the instructions which, when executed on at least one processor, cause the at least one processor to carry out the actions described herein, as performed by the radio network node <NUM>. In some embodiments, the computer-readable storage medium may be a non-transitory or transitory computer-readable storage medium.

In some embodiments a more general term "radio network node" is used and it can correspond to any type of radio network node or any network node, which communicates with a wireless device and/or with another network node. Examples of network nodes are NodeB, Master eNB, Secondary eNB, a network node belonging to Master cell group (MCG) or Secondary Cell Group (SCG), base station (BS), multistandard radio (MSR) radio node such as MSR BS, eNodeB, network controller, radio network controller (RNC), base station controller (BSC), relay, donor node controlling relay, base transceiver station (BTS), access point (AP), transmission points, transmission nodes, Remote Radio Unit (RRU), Remote Radio Head (RRH), nodes in distributed antenna system (DAS), core network node e.g. Mobility Switching Centre (MSC), Mobile Management Entity (MME) etc., Operation and Maintenance (O&M), Operation Support System (OSS), Self-Organizing Network (SON), positioning node e.g. Evolved Serving Mobile Location Centre (E-SMLC), Minimizing Drive Test (MDT) etc..

In some embodiments the non-limiting term wireless device or UE is used and it refers to any type of wireless device communicating with a network node and/or with another UE in a cellular or mobile communication system. Examples of UE are target device, device-to-device (D2D) UE, proximity capable UE (aka ProSe UE), machine type UE or UE capable of machine to machine (M2M) communication, PDA, PAD, Tablet, mobile terminals, smart phone, laptop embedded equipped (LEE), laptop mounted equipment (LME), USB dongles etc..

The embodiments are described for <NUM>. However, the embodiments are applicable to any RAT or multi-RAT systems, where the UE receives and/or transmit signals (e.g. data) e.g. LTE, LTE FDD/TDD, WCDMA/HSPA, GSM/GERAN, Wi Fi, WLAN, CDMA2000 etc..

As will be readily understood by those familiar with communications design, that functions means or modules may be implemented using digital logic and/or one or more microcontrollers, microprocessors, or other digital hardware. In some embodiments, several or all of the various functions may be implemented together, such as in a single application-specific integrated circuit (ASIC), or in two or more separate devices with appropriate hardware and/or software interfaces between them. Several of the functions may be implemented on a processor shared with other functional components of a wireless device or network node, for example.

Alternatively, several of the functional elements of the processing means discussed may be provided through the use of dedicated hardware, while others are provided with hardware for executing software, in association with the appropriate software or firmware. Thus, the term "processor" or "controller" as used herein does not exclusively refer to hardware capable of executing software and may implicitly include, without limitation, digital signal processor (DSP) hardware, read-only memory (ROM) for storing software, random-access memory for storing software and/or program or application data, and non-volatile memory. Designers of communications devices will appreciate the cost, performance, and maintenance trade-offs inherent in these design choices.

With reference to <FIG>, in accordance with an embodiment, a communication system includes a telecommunication network <NUM>, such as a 3GPP-type cellular network, which comprises an access network <NUM>, such as a radio access network, and a core network <NUM>. The access network <NUM> comprises a plurality of base stations 3212a, 3212b, 3212c, such as NBs, eNBs, gNBs or other types of wireless access points being examples of the radio network node <NUM> herein, each defining a corresponding coverage area 3213a, 3213b, 3213c. Each base station 3212a, 3212b, 3212c is connectable to the core network <NUM> over a wired or wireless connection <NUM>. A first user equipment (UE) <NUM>, being an example of the UE <NUM>, located in coverage area 3213c is configured to wirelessly connect to, or be paged by, the corresponding base station 3212c. A second UE <NUM> in coverage area 3213a is wirelessly connectable to the corresponding base station 3212a.

The wireless connection <NUM> between the UE <NUM> and the base station <NUM> is in accordance with the teachings of the embodiments described throughout this disclosure. One or more of the various embodiments improve the performance of OTT services provided to the UE <NUM> using the OTT connection <NUM>, in which the wireless connection <NUM> forms the last segment. More precisely, the teachings of these embodiments may achieve a SI transmission procedure avoiding collision of SI messages , or position SI message, and thereby provide benefits such as improved battery time, and better responsiveness at the UE side.

It will be appreciated that the foregoing description and the accompanying drawings represent non-limiting examples of the methods and apparatus taught herein. As such, the apparatus and techniques taught herein are not limited by the foregoing description and accompanying drawings. Instead, the embodiments herein are limited only by the following claims.

For SI message acquisition PDCCH monitoring occasion(s) are determined according to searchSpaceOtherSystemInformation. If searchSpaceOtherSystemInformation is set to zero, PDCCH monitoring occasions for SI message reception in SI-window are same as PDCCH monitoring occasions for SIB1 where the mapping between PDCCH monitoring occasions and SSBs is specified in TS <NUM>[<NUM>]. If searchSpaceOtherSystemInformation is not set to zero, PDCCH monitoring occasions for SI message are determined based on search space indicated by searchSpaceOtherSystemInformation. PDCCH monitoring occasions for SI message which are not overlapping with UL symbols (determined according to tdd-UL-DL-ConfigurationCommon) are sequentially numbered from one in the SI window. The [x×N+K]th PDCCH monitoring occasion (s) for SI message in SI-window corresponds to the Kth transmitted SSB, where x = <NUM>, <NUM>,. X-<NUM>, K = <NUM>, <NUM>,. N, N is the number of actual transmitted SSBs determined according to ssb-PositionsInBurst in SIB1 and X is equal to CEIL(number of PDCCH monitoring occasions in SI-window/N). The actual transmitted SSBs are sequentially numbered from one in ascending order of their SSB indexes. The UE assumes that, in the SI window, PDCCH for an SI message is transmitted in at least one PDCCH monitoring occasion corresponding to each transmitted SSB and thus the selection of SSB for the reception SI messages is up to UE implementation. When acquiring an SI message, the UE shall:.

Claim 1:
A method performed by a user equipment, UE, (<NUM>) for determining a start position of a system information, SI, window used for acquiring a SI message in a wireless communication network (<NUM>), wherein SI messages are transmitted in periodically occurring SI windows, characterized in that one or more SI messages are scheduled using a first or a second list of scheduling information, the method comprising:
- if an SI message is scheduled using the first list of scheduling information, determining (<NUM>) the start position of the SI window based on the order of entry of said SI message in a list of SI messages configured by the first list of scheduling information; else
- if an SI message is scheduled using the second list of scheduling information, determining (<NUM>) the start position of the SI window by taking an input parameter into account, wherein the input parameter is a value of a field in a message received from a radio network node, said value being configured for said SI message by the radio network node, whereby the UE determines the start position of the SI window based on an integer value x, which integer value x is calculated by taking the received input parameter minus <NUM> and multiplying it with a value representing the window length of the SI window, wherein the SI window starts at a slot #a, where a = x mod N, in the radio frame for which SFN mod T = FLOOR(x/N), where T is the periodicity of the concerned SI message and N is the number of slots in a radio frame.