TWI773309B - User equipment end of narrow band internet of things - Google Patents

Abstract

The present invention discloses a user equipment (UE) of a Narrow Band Internet of Things (NB-IoT). The UE includes a memory, a computing circuit, and a wireless signal transceiver circuit. The memory stores a program code which relates to a function of the UE. The computing circuit is coupled to the memory and configured to perform the function of the UE by executing the program code stored in the memory. The wireless signal transceiver circuit is coupled to the computing circuit. The computing circuit receives signals from a base station via the wireless signal transceiver circuit to synchronize with the base station and receives at least one system information parameter from the base station. The at least one system information parameter contains a maximum number of repetitions, a period, and an offset of the Narrowband Physical Downlink Control Channel (NPDCCH) search space, and the computing circuit creates a scheduling list based on the at least one system information parameter.

Description

User equipment operating on NB-IoT

The present invention relates to Narrow Band Internet of Things (Narrow Band Internet of Things, hereinafter referred to as NB-IoT), in particular to user equipment (user equipment, hereinafter referred to as UE) operating in the Narrow Band Internet of Things.

FIG. 1 is a schematic diagram of downlink scheduling of conventional NB-IoT. In the figure, "SFN" stands for system frame number, also known as radio frame number; "SI window" (SI scheduling window) is used to indicate the scheduled system message (system message). information, SI) types (for example, three system messages are shown in Figure 1: SI-1, SI-2 and SI-3). Each system frame includes 10 subframes, and the types of channels, information or signals that each subframe can carry include: Narrowband primary synchronization signal (Narrowband) Primary Synchronization Signal, NPSS), Narrowband Secondary Synchronization Signal (NSSS), Narrowband Physical Broadcast Channel (NPBCH), Narrowband System Information Block Type 1 (Narrowband System Information Block Type1, SIB1-NB, Abbreviated as SIB1), system information type 1 (system information type 1, SI-1), system information type 2 (system information type 2, SI-2), system information type 3 (system information type 3, SI-3), and Narrowband Physical Downlink Control Channel (NPDCCH). A legend for these channels is shown at the top of FIG. 1 . For example, subframe 0 (subframe numbered 0, that is, the 0th subframe of the 0th SFN) carries NPBCH (symbol "M"), subframe 44 (subframe numbered 44) frame, that is, the 4th subframe of the 4th SFN) carries SIB1 (symbol "B"), subframe 121 (subframe numbered 121, that is, the 1st subframe of the 12th SFN) Not used (blank).

Among the above channels, messages or signals, NPSS, NSSS, NPBCH, and SIB1 appear at fixed positions in a specific period, so the channel, message or signal type of the subframe can be known from the subframe number. For example, NPSS appears in the 5th subframe of each SFN, NSSS appears in the 9th subframe of even-numbered SFNs, NPBCH appears in the 0th subframe of each SFN, and SIB1 appears in the interval of SFNs. The 4th subframe (the period of SIB1 in this example is 16 SFNs).

Because the priority of NPSS, NSSS, NPBCH, and SIB1 is higher than that of SI-x (x is 1, 2, or 3) and NPDCCH, after the subframes of NPSS, NSSS, NPBCH, and SIB1 are determined, SI-x and NPDCCH Then use the remaining unused subframes in priority order (the priority order of SI-x is higher than that of NPDCCH). For example, SI-1 appears in the SI scheduling window starting with SFN=0, using subframes {1, 2, 3, 6, 7, 8, 11, 12}, and repeating after 8 radio frames once. After all SI-x are arranged, the NPDCCH search space (search space) is arranged in the remaining subframes.

For the example in Figure 1, a set of NPDCCH search spaces occurs once every 64 subframes (that is, the period T=64 subframes), and each occurrence will occupy 16 subframes (that is, the maximum number of repetitions ( maximum number of repetitions) R _max = 16 subframes). The maximum number of repetitions is a parameter set by the base station for the NPDCCH, and the actual number of repetitions may be different in each NPDCCH transmission, which is determined by the base station according to the channel conditions of the UE. The first NPDCCH group (repetition) should start from subframe 0, but because NPSS, NSSS, NPBCH, SIB1 and S1-1 have higher priority than NPDCCH, the first NPDCCH group actually starts from subframe 13, using {13, 14, 16, 17, 18, 19, 21, 22, 23, 26, 27, 28, 31, 32, 33, 34} etc. 16 subframes. Similarly, the second NPDCCH group should start at subframe 64 (since T=64), but actually starts at subframe 66, using {66, 67, 68, 71, 72, 73, 74, 76, 77, 78, 79, 93, 94, 96, 97, 98} and other 16 subframes.

In the example of FIG. 1 , the offset (offset) of the NPDCCH is 0 subframes. If the offset is 3 subframes, the second NPDCCH group becomes supposed to start from subframe 67, but the first NPDCCH group still starts from subframe 13 (because subframe 3 to subframe 12 have been use).

The NB-IoT UE needs to know the following information when scheduling: 1. Whether a target subframe is an NPDCCH candidate subframe (candidate), if so, the target subframe is the subframe of an NPDCCH group (that is, the target subframe is in the NPDCCH group) ordinal position). Taking the schedule of FIG. 1 as an example, the target subframe numbered 14 is the second subframe of the first NPDCCH group, and the target subframe numbered 71 is the fourth subframe of the second NPDCCH group. 2. The start subframe of the NPDCCH group closest to the target subframe. Taking the schedule of FIG. 1 as an example, the start subframe of the first NPDCCH group is subframe 13 , and the start subframe of the second NPDCCH group is subframe 66 . 3. The end subframe of the NPDCCH group closest to the target subframe. Taking the schedule of FIG. 1 as an example, the ending subframe of the first NPDCCH group is subframe 34 , and the ending subframe of the second NPDCCH group is subframe 98 .

In order to obtain the above information, the UE needs to start from an NPDCCH group (that is, a subframe numbered T*L+O, where T is the period, O is the offset, L=0, 1, 2, 3 ...) Check one by one whether the subframes are available for downlink transmission (described in the message "downlinkBitmap-r13" of SIB1) and are not used. When it is confirmed that a certain subframe is available for downlink transmission and is not used, the NPDCCH may be scheduled to be received in that subframe. This method is referred to in this specification as an "iteration over subframes" method.

The UE needs to obtain the above-mentioned information within a subframe (that is, about 1ms), but the UE must also complete other tasks including physical layer (PHY) scheduling and control within a subframe. In other words, the UE has to perform a lot of calculations in a limited time, and the number of iterations of the above-mentioned "iteration by subframe" method will increase with the maximum number of repetitions _Rmax , and _Rmax may be as high as 2048.

The above-mentioned various restrictions or requirements constitute a great burden for the UE with low cost and low power consumption, so the UE needs a more efficient scheduling method.

In view of the deficiencies of the prior art, one object of the present invention is to provide a UE operating in NB-IoT to improve the deficiencies of the prior art.

An embodiment of the present invention discloses a user equipment. The user equipment operates in a narrowband Internet of Things and includes a memory, a computing circuit, and a wireless signal transceiving circuit. The memory stores a code related to the functions of the user equipment. The computing circuit is coupled to the memory for executing the code stored in the memory to execute the function of the user equipment. The wireless signal transceiving circuit is coupled to the computing circuit. The computing circuit receives a signal sent by a base station through the wireless signal transceiving circuit and is synchronized with the base station, and receives at least one system information parameter from the base station. The at least one system information parameter includes a maximum repetition number, a period and an offset of the narrowband physical downlink control channel search space, and the calculation circuit creates a scheduling list according to the at least one system information parameter.

The UE of the NB-IoT of the present invention improves the scheduling efficiency of the UE by establishing a list and searching for a list. Compared with the conventional technology, because the UE of the NB-IoT of the present invention does not need to check the subframes one by one in the time domain, the performance of the UE can be improved to ensure that the UE completes all necessary calculations in one subframe. The present invention further proposes a method for establishing a schedule list to further reduce the memory usage of the list, so that the UE completed by the present invention is more competitive.

With regard to the features, implementations and effects of the present invention, embodiments are described in detail as follows in conjunction with the drawings.

The technical terms used in the following description refer to the common terms in the technical field. If some terms are described or defined in this specification, the interpretation of these terms is subject to the descriptions or definitions in this specification.

Part or all of the process of the UE-side scheduling method and the scheduling list creation method of the NB-IoT of the present invention can be in the form of software and/or firmware, and can be implemented by the NB-IoT UE of the present invention or its equivalent device On the premise of not affecting the full disclosure and practicability of the method invention, the following description of the method invention will focus on the step content rather than the hardware.

FIG. 2 is a functional block diagram of an embodiment of a UE of NB-IoT according to the present invention. The UE 100 includes a wireless signal transceiving circuit 110 , a computing circuit 120 and a memory 130 . The computing circuit 120 may be a circuit or electronic component with program execution capability, such as a central processing unit, a microprocessor or a micro-processing unit, which performs the functions of the UE 100 by executing the program code or program instructions stored in the memory 130 . FIG. 3 is a flowchart of an embodiment of a UE-side scheduling method according to the present invention. By executing the flowchart of FIG. 3 , the computing circuit 120 can know whether a target subframe n_sf_target is an NPDCCH candidate subframe. Please refer to Figure 2 and Figure 3 for the following content.

Step S410: The UE 100 is synchronized with a base station (cell) (not shown). The computing circuit 120 receives the signal sent by the base station through the wireless signal transceiving circuit 110, and synchronizes with the base station according to at least NPSS and NSSS. The details of the synchronization between the UE 100 and the base station are well known to those skilled in the art, and thus will not be repeated here.

Step S420 : the computing circuit 120 receives at least one system information parameter from the base station through the wireless signal transceiving circuit 110 . The system information parameters are, for example, NPSS, NSSS, NPBCH, SIB1, and SI-x, and the system information parameters include the period T of the NPDCCH search space, the maximum number of repetitions R _max , and the offset O. Those with ordinary knowledge in the art can obtain the period T, the maximum number of repetitions R _max and the offset O of the NPDCCH search space from the system information parameters according to the NB-IoT specification, the details of which will not be repeated.

Step S430: The computing circuit 120 creates a list according to the system information parameter, and the list records a plurality of subframes. More specifically, the calculation circuit 120 can know the subframes occupied by NPSS, NSSS, NPBCH, SIB1, and SI-x and their numbers according to the system information parameters. The subframe that is used (that is, the available subframe) and its number. For example, a list corresponding to the schedule of FIG. 1 can be shown in Table 1 below: Table 1: index 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 subframe 13 14 16 17 18 19 twenty one twenty two twenty three 26 27 28 31 32 33 34 index 16 17 18 19 20 twenty one twenty two twenty three twenty four 25 26 27 28 29 30 31 subframe 36 37 38 39 41 42 43 46 47 48 51 52 53 54 56 57 index 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 … subframe 58 59 61 62 63 66 67 68 71 72 73 74 76 77 78 …

Each available subframe listed in the list may be used to carry the NPDCCH and corresponds to an index. In some embodiments, the indices and the numbers of available subframes are monotonically increasing, but not limited thereto. In some embodiments, the list may be stored in the memory 130 in the form of an array, the numbers of the available subframes are the elements of the array, and the index is the index of the array.

），此差值代表索引i1與索引i2之間的可用子訊框的個數。舉例來說，distance(0, 1)=1-0=1，distance(32, 37)=37-32=5。 4.       函式add(i, d)：用於找出與索引i，距離d個（或中間隔d-1個）可用子訊框的索引。舉例來說，add(1, 2)=1+2=3。Some functions are defined here, which are part of the code or program instructions stored in the memory 130, to illustrate the present case more clearly. 1. Function subfn2index(n_sf): used to find the index of the available subframe that is closest to and not smaller than subframe n_sf. For example, subfn2index(13)=0, subfn2index(15)=2, subfn2index(20)=6. 2. The function index2subfn(i): used to find the available subframes at index i. For example, index2subfn(2)=16, index2subfn(25)=48. 3. Function distance(i1, i2): used to find the difference between index i1 and index i2 (

), the difference represents the number of available subframes between index i1 and index i2. For example, distance(0, 1)=1-0=1, distance(32, 37)=37-32=5. 4. The function add(i, d): used to find the index of the available subframes at a distance of d (or intermediate interval d-1) from index i. For example, add(1, 2)=1+2=3.

+O                                                 (1)Step S440: Calculate the number n_sf_start of the start subframe of the target NPDCCH group according to the number of the target subframe n_sf_target, the period T and the offset O. In this step, the calculation circuit 120 may calculate the number n_sf_start according to equation (1). n_sf_start=

+O (1)

+0=1*64=64。如圖1的排程所示，目標NPDCCH組即為第二NPDCCH組，而因為對應編號n_sf_start=64的子訊框被SIB1占用，所以編號的子訊框並非實際的起始子訊框（子訊框66才是實際的起始子訊框）。For example, when the number of the target subframe n_sf_target is 77, the maximum number of repetitions R _max =16, the period T=64 and the offset O=0, then the number n_sf_start=

+0=1*64=64. As shown in the schedule in Figure 1, the target NPDCCH group is the second NPDCCH group, and because the subframe corresponding to n_sf_start=64 is occupied by SIB1, the numbered subframe is not the actual start subframe (subframe). Frame 66 is the actual start subframe).

Step S450: The calculation circuit 120 uses the number n_sf_start to find the start index i_start of the corresponding start subframe in the list. Please refer to FIG. 4 , which is a detailed flowchart of step S450 . In step S452, the calculation circuit 120 determines whether the list contains the number n_sf_start. If yes, the calculation circuit 120 executes step S454; if not, the calculation circuit 120 executes step S456. In step S454, the calculation circuit 120 uses the index corresponding to the number n_sf_start as the start index i_start; more specifically, step S454 uses subfn2index(n_sf_start) to obtain i_start. For example, i_start=subfn2index(66)=37. In step S456, the calculation circuit 120 uses the index corresponding to the adjacent sub-frame that is closest to and not smaller than the number n_sf_start as the start index i_start. For example, the adjacent subframe that is closest to and not less than the number n_sf_start=64 is subframe 66, and the index of subframe 66 is i_start=37; in other words, step S456 can also use subfn2index(n_sf_start) to obtain i_start , that is, i_start=subfn2index(64)=37. In step S450, the computing circuit 120 may use a binary search method (Binary Search) to find the start index i_start.

Step S460: The calculation circuit 120 finds the target index i_target corresponding to the target subframe n_sf_target in the list. Similar to the previous step, when the indices and the subframe numbers are both monotonically increasing, the calculation circuit 120 finds the index in the list that is closest to and not smaller than the target subframe n_sf_target. When n_sf_target=77, i_target=subfn2index(77)=45.

Step S470: The calculation circuit 120 determines whether the target subframe n_sf_target is in the range covered by the target NPDCCH group by determining whether the difference between the start index i_start and the target index i_target is less than the maximum repetition number _Rmax . The range covered by an NPDCCH group refers to all subframes between the start subframe and the end subframe of the NPDCCH group. For example, in the example of FIG. 1 , the range covered by the first NPDCCH group is subframe 13 to subframe 34 , and the range covered by the second NPDCCH group is subframe 66 to subframe 98 .

Please refer to FIG. 5, which is a detailed flow of step S470. In step S472 , the calculation circuit 120 determines whether i_target - i_start is less than the maximum number of repetitions R _max , that is, determines whether distance(i_target, i_start) is less than R _max (step S472 ). If yes, the calculation circuit 120 judges that the target subframe n_sf_target is within the range covered by the target NPDCCH group (step S474 ); otherwise, the calculation circuit 120 judges that the target subframe n_sf_target is not within the range covered by the target NPDCCH set (step S474 ) S476). Following the above example, since distance(i_target, i_start)=45-37=8<R _max =16, the calculation circuit 120 can determine that the target subframe n_sf_target is in the second NPDCCH group (as shown in FIG. 1 , 66<n_sf_target = 77 < 98).

Step S480 : The calculation circuit 120 determines whether the target subframe n_sf_target is an NPDCCH candidate subframe according to the target index i_target and the number of the target subframe n_sf_target. The calculation circuit 120 first uses the target index i_target to query the corresponding subframe n_sf_temp in the list (ie, n_sf_temp=index2subfn(i_target)), and then determines whether the number of the target subframe n_sf_target is equal to the number of the subframe n_sf_temp. If they are equal (that is, n_sf_target=n_sf_temp), the target subframe n_sf_target is an NPDCCH candidate subframe; if not (that is, n_sf_target≠n_sf_temp), the target subframe n_sf_target is not an NPDCCH candidate subframe. For example, although the target subframes n_sf_target numbered 75 and 76 both correspond to the target index i_target=44 (that is, subfn2index(75)=subfn2index(76)=44), the subframe corresponding to the target index i_target=44 The number of n_sf_temp is 76 (that is, index2subfn(44)=76), so the calculation circuit 120 can know that the target subframe n_sf_target numbered 75 is not the NPDCCH candidate subframe, but the target subframe n_sf_target numbered 76 is the NPDCCH candidate subframe.

After the calculation circuit 120 completes step S480 in FIG. 3 , it can know whether the target subframe n_sf_target is a NPDCCH candidate subframe. In step S490, when it is determined that the target subframe n_sf_target is the NPDCCH candidate subframe, the target subframe n_sf_target is received. In step S495, when it is determined that the target subframe n_sf_target is not the NPDCCH candidate subframe, the target subframe n_sf_target is not received.

6 is a flowchart of another embodiment of the UE scheduling method according to the present invention. By executing the flowchart calculation circuit 120 in FIG. 6 , the start subframe of the NPDCCH group closest to the target subframe n_sf_target can be obtained.

Step S810: The calculation circuit 120 determines whether the target subframe n_sf_target is in the range covered by the target NPDCCH group. If yes, the calculation circuit 120 executes step S820; if not, the calculation circuit 120 executes step S830. After the calculation circuit 120 completes the step S820 or the step S830, the flow of FIG. 6 is ended (step S840).

Step S820: The calculation circuit 120 uses the start index i_start to find the start subframe of the target NPDCCH group in the list. For example, following the above example, since the target subframe n_sf_target numbered 77 is in an NPDCCH group (obtained in step S470 ), the calculation circuit 120 directly uses the starting point obtained in step S450 in step S820 Index i_start (=37) to find the subframe (=66) corresponding to the start index i_start in the list (ie, index2subfn(37)=66). The subframe corresponding to the start index i_start is the start subframe of the target NPDCCH group.

Step S830: The calculation circuit 120 finds the start subframe of the next NPDCCH group next to the target NPDCCH group. Step S830 includes sub-steps S832, S834 and S836.

+O                                                (2)Step S832: The calculation circuit 120 calculates the number n_sf_start' of the start subframe of the next NPDCCH group according to the number of the target subframe n_sf_target and the period T. In this step, the calculation circuit 120 may calculate the number n_sf_start' according to equation (2). n_sf_start'=

+O (2)

+0=1*64=64。如圖1的排程所示，目標NPDCCH組的次一NPDCCH組即為第二NPDCCH組，而第二NPDCCH組緊鄰第一NPDCCH組（亦即第一及第二組中間沒有其他NPDCCH組）。For example, when the number of the target subframe n_sf_target is 44, the maximum number of repetitions R _max =16, the period T=64 and the offset O=0, then the number n_sf_start'=

+0=1*64=64. As shown in the schedule of FIG. 1 , the next NPDCCH group of the target NPDCCH group is the second NPDCCH group, and the second NPDCCH group is adjacent to the first NPDCCH group (ie, there is no other NPDCCH group between the first and second groups).

Step S834: The calculation circuit 120 uses the number n_sf_start' to find the start index i_start' of the start subframe corresponding to the next NPDCCH group in the list. Following the above example, the calculation circuit 120 searches the list with the number n_sf_start'=64, and obtains the start index i_start'=37 (ie, subfn2index(64)=37).

Step S836: The calculation circuit 120 uses the start index i_start' to find the start subframe of the next NPDCCH group in the list. Continuing from the above example, the calculation circuit 120 searches the list with the start index i_start'=37, and obtains the number (=66) of the start subframe (ie, index2subfn(37)=66).

To sum up, by creating the list and searching the list, the UE does not need to check the subframes one by one, thus speeding up the operation. However, since SI-x is at most 40960 subframes, the array in memory 130 used to represent the list has at most 40960 elements. When each element is represented by a 16-bit integer, the array used to represent the list needs to occupy (16/8)*40960=81920 bytes. Such memory usage constitutes a great burden for UEs with low cost and low power consumption. Therefore, the present invention further proposes a method for establishing a schedule list to reduce memory usage (ie, reduce list size), as described in detail below.

FIG. 7 is another schematic diagram of downlink scheduling of the conventional NB-IoT. From the specification of NB-IoT, it can be found that the appearance of NPSS, NSSS, NPBCH, SIB1 and SI-x (x is 1, 2 or 3) has rules to follow, so scheduling can be simplified according to the specification of NB-IoT list to reduce memory usage.

FIG. 8 is a flowchart of a method for establishing a schedule list according to the present invention. First, the calculation circuit 120 synchronizes with the base station (step S410 ), and then receives at least one system information parameter from the base station, such as NPSS, NSSS, NPBCH, SIB1, and SI-x (step S420 ). Steps S410 and S420 have been discussed above, so they are not repeated here.

Step S1110: Create a plurality of sublists according to the distribution of SI-x and SIB1. If 160 subframes are used as a sublist, it can be found that in the case of no SI offset (SI offset), the type of the sublist is 2*(the number of SI-x+1). In this example, the number of SI-x is 3, so there are 8 types of sublists in total. The eight seed lists are derived from the distribution of SIB1 and SI-x, as shown in Table 2 below.

Table 2: SI-x/SIB1 Has SIB1 no SIB1 no SI-x 0 1 SI-1 only 2 3 SI-2 only 4 5 SI-3 only 6 7

Step S1120: Designate a sub-list code (code) for each sub-list. Codes 0 to 7 in Table 2 are the codes of the sublists. For example, sub-list 1 describes that 160 sub-frames have neither SIB1 nor SI-x, as shown in sub-frames 480-639 in Figure 7; sub-list 6 describes that 160 sub-frames have SIB1 and SI-3, As shown in subframes 320-479 of FIG. 7 . Table 3 below shows part of the contents of each sublist. Each element of the sublist corresponds to a sublist index and represents an available subframe. Note that the subframes of each sublist are numbered starting from 0. For example, the first available subframe of sublist 6 is subframe 13 (since subframes 0-12 are used by NPBCH, SIB1, NPSS, NSSS and SI-3), and the first available subframe of sublist 1 The available subframe is subframe 1 (since subframe 0 is used by NPBCH).

table 3: sub-manifest code sublist number of elements 0 {1, 2, 3, 6, 7, 8, 11, 12, 13, 14, 16, 17, ...} 112 1 {1, 2, 3, 4, 6, 7, 8, 11, 12, 13, 14, 16, 17, ...} 120 2 {13, 14, 16, ..., 77, 78, 79, 93, 94, 96, ...} 96 3 {12, 13, 14, 16, ..., 77, 78, 79, 92, 93, 94, 96, ...} 104 4 {13, 14, 16, ..., 77, 78, 79, 81, 82, 83, 86, ...} 104 5 {12, 13, 14, 16, ..., 77, 78, 79, 81, 82, 83, 84, 86, ...} 96 6 {13, 14, 16, ..., 77, 78, 79, 81, 82, 83, 86, ...} 104 7 {12, 13, 14, 16, ..., 77, 78, 79, 81, 82, 83, 84, 86, ...} 96

Step S1130: Calculate the number of elements in each sublist. The number of elements in Table 3 represents the number of available subframes of the sublist. For example, sub-list 2 has elements 13, 14, 16, ..., corresponding to sub-list indices 0, 1, 2, ... respectively, and sub-list 2 has a total of 96 elements, in other words, corresponding to 160 sub-frames of sub-list 2 There are a total of 96 available subframes.

Step S1140: Create a list according to the system information parameters, the sub-list code and the number of elements. Table 4 is an example of a checklist.

Table 4: list index element group({sublist code, accumulated value}) 0 {2, 0} 1 {5, 96} 2 {6, 192} 3 {1, 296} 4 {2, 416} 5 {5, 512} 6 {6, 608} 7 {1, 712} … …

The list has a plurality of element groups, and each element group contains the sub-list code and the accumulated value. For example, the sub-list code of element group 0 is 2, and the accumulated value is 0; the sub-list code of element group 3 is 1, and the accumulated value is 296. The list in Table 4 shows that subframes 0~159 (corresponding to list index 0) can be represented by sublist 2, subframes 160~319 (corresponding to list index 1) can be represented by sublist 3, and subframes 320~ 479 (corresponding to manifest index 2) can be represented by sub-list 6, and so on. Because SI-x has a maximum of 40960 subframes, the list has at most 40960/160=256 element groups (corresponding to list indices 0~255).

The accumulated value is the accumulation of the number of elements in the sub-list. For example, because the list index 0 corresponds to the first sub-list (the example in Table 4 is sub-list 2), the accumulation of the number of elements in the sub-list is 0; Index 1 corresponds to the second sublist (the example in Table 4 is sublist 5), and the accumulated value is the previous accumulated value (0 in the example of Table 4) and the elements of the previous sublist (the example in Table 4 is sublist 2) The sum of the number (the example of Table 3 is 96) (0+96=96); the list index 2 corresponds to the third sub-list (the example of Table 4 is sub-list 6), and the accumulated value is the previous accumulated value (the table of The example is 96) and the number of elements (96 in the example of Table 3) of the previous sublist (the example in Table 4 is sublist 5) (96+96=192); and so on.

Please note that Tables 2-4 are related to system information parameters, and those with ordinary knowledge in the art can generate corresponding Tables 2-4 according to different system information parameters according to the above contents. Comparing the list in Table 1 and the list in Table 4, the list in Table 1 directly records the subframe, while the list in Table 4 records the subframe indirectly (the subframe is recorded in the sublist). Therefore, the list in Table 1 can be viewed as is first-order (the content of the list is a subframe), and the list in Table 4 can be regarded as a second-order (the content of the list contains the code of the sublist, the content of the sublist contains the subframe, and the sublist is shown in Table 3). In response to the change of the list from the first order to the second order, the operation details of the functions 1 to 3 in the aforementioned four functions can be illustrated by the flow charts in FIGS. 9 to 11 .

FIG. 9 shows the operation details of step S450 based on the second-order list (including the operation details of the function subfn2index()), including steps S1210-S1230. Note that the index i is adjusted to include the list index i_p and the sub-list index i_sf for the second-order list. For example, the start index i_start includes the start list index i_start_p and the start sublist index i_start_sf.

。「mod」為取模操作（modulo operation）的簡稱。「mod 256」是因為排程的週期為40960個子訊框，而且當以160個子訊框為一個單位，則排程的週期為256個單位。舉例來說，當n_sf_start=66，i_start_p=0 mod 256=0；當n_sf_start=166，i_start_p=1 mod 256=1。Step S1210 : The calculation circuit 120 calculates the start list index i_start_p according to the number n_sf_start , the period of SIB1 (160 ms), and the number of element groups of the list (256).

. "mod" is short for modulo operation. "mod 256" is because the scheduled period is 40960 subframes, and when 160 subframes are used as a unit, the scheduled period is 256 units. For example, when n_sf_start=66, i_start_p=0 mod 256=0; when n_sf_start=166, i_start_p=1 mod 256=1.

Step S1220: The calculation circuit 120 finds the target sublist in the list according to the start list index i_start_p. Taking the list in Table 4 as an example, the start list index i_start_p=0 corresponds to the target sub-list 2, the start list index i_start_p=1 corresponds to the target sub-list 5, and so on.

Step S1230: The calculation circuit 120 calculates the remainder Rm (=n_sf_start mod 160) of dividing the number n_sf_start by the period (160ms) of the SIB1, and finds the sublist index corresponding to the element that is closest to but not less than the remainder Rm in the target sublist i_start_sf. When n_sf_start=170, then Rm=10, and the sublist indices i_start_sf corresponding to Rm=10 in sublists 0~7 of Table 3 are 6, 7, 0, 0, 0, 0, 0, 0, respectively.

10 shows the operation details of step S480 based on the second-order list, including steps S1310-S1360, wherein steps S1310-S1330 are the operation details of the function index2subfn(), and the target index i_target includes the target list index i_target_p and the target sublist index i_target_sf.

Step S1310: The calculation circuit 120 finds the sub-list code in the list according to the target list index i_target_p of the target index i_target. This step can be accomplished by looking up Table 4, for example, when the target list index i_target_p=3, the sublist code is 1.

Step S1320: The calculation circuit 120 finds the sub-list from Table 3 according to the sub-list code. For example, a sublist code of 1 corresponds to a sublist with 120 elements.

Step S1330: The calculation circuit 120 finds the middle subframe n_sf_found in the sublist according to the target sublist index i_target_sf of the target index i_target. For example, if sub-list 1 is found in the previous step, sub-frame 2 will be found according to the target sub-list index i_target_sf=1.

Steps S1340 to S1360: The calculation circuit 120 determines whether the middle subframe n_sf_found is equal to the target subframe n_sf_target. If they are equal (YES in step S1340 ), the calculation circuit 120 determines that the target subframe n_sf_target is the NPDCCH candidate subframe (step S1350 ); if not (NO in step S1340 ), the calculation circuit 120 determines the target subframe n_sf_target The subframes are not NPDCCH candidate subframes (step S1360).

Fig. 11 is part of the operation details of step S470 based on the second-order list; more specifically, step S1400 "judging whether the difference between the start index i_start and the target index i_target is less than the maximum number of repetitions _Rmax " is a sub-step of step S470 , including steps S1410-S1460, wherein steps S1410-S1450 are the operation details of the function distance() based on the second-order list.

Step S1410: The calculation circuit 120 finds the first accumulated value of the first element group in the list according to the start list index i_start_p of the start index i_start. For example (refer to Table 4), assuming i_start_p=4, the first element group is {2, 416}, and the first accumulated value is 416.

Step S1420: The calculation circuit 120 adds the first accumulated value to the start sublist index i_start_sf to generate the first sum S1. Following the above example, when the first accumulated value is 416 and the start sublist index i_start_sf=5, then the first sum S1=416+5=421.

Step S1430: The calculation circuit 120 finds the second accumulated value of the second element group in the list according to the target list index i_target_p of the target index i_target. For example (refer to Table 4), assuming i_target_p=5, the first element group is {5, 512}, and the second accumulated value is 512.

Step S1440: The calculation circuit 120 adds the second accumulated value to the target sublist index i_target_sf to generate the second sum S2. Following the above example, when the second accumulated value is 512 and the target sublist index i_target_sf=17, then the second sum S2=512+17=529.

Step S1450: The calculation circuit 120 calculates the difference between the first sum and the second sum to obtain the number M. That is to say, following the above example, M=S2-S1=529-421=108. In other words, in the examples of Tables 3 and 4, there are 108 available subframes between the first index i_first ({4, 5}) and the second index i_second ({5, 17}).

Step S1460 : the calculation circuit 120 compares the number M of available subframes with the maximum number of repetitions R _max .

After using the above method to change the list to second-order, take SI-x including SI-1, SI-2 and SI-3 as an example (that is, there are 8 sub-lists, as shown in Table 3). The memory size occupied is (160+1)*8=1288 bytes (“+1” represents the number of elements, and one byte is required for the number of elements and each subframe); while the list occupies The memory size is 40960/160*3=768 bytes (one byte is required for the sublist code, and two bytes for the accumulated value). In short, the second-order list only needs 1288+768=2056 bytes in total, which is only about 2.5% of the 81920 memory space required by the first-order list, so using the second-order list can greatly reduce the memory usage. , making UE more competitive.

The above processes, functions and data can be completed by using C language, but not limited thereto. For example, the sub-list in Table 3 can be represented by the structure shown in Figure 12 in C language, where "available" is the number of elements, the array "n_sf[160]" is the sub-list, and the array "pattern[]" The index is the sub-list code; the list in Table 4 can be represented by the structure shown in Figure 13 in C language, where the array "available[256]" is the list, "pattern" is the sub-list code, and "offset" is the accumulated value; FIG. 14 shows an example of index i (including list index i_p and sub-list index i_sf) and the above four functions implemented in C language. Those skilled in the art can understand the meaning of the programming language in FIG. 14 , so it is not repeated here.

Those with ordinary knowledge in the art can know how to create a sub-list according to the distribution of SI-x and SIB1 when there is an SI offset based on the above description, so it is not repeated here.

Since a person with ordinary knowledge in the technical field can understand the implementation details and changes of the method invention in this application through the disclosure content of the device invention in this application, in order to avoid redundant repetition, the disclosure requirements and practicability of the method invention are not affected. On the premise, repeated explanations are omitted here. Please note that the shapes, sizes, proportions and sequence of steps of the components in the preceding figures are only illustrative and are for those skilled in the art to understand the present invention, rather than limiting the present invention.

Although the embodiments of the present invention are described above, these embodiments are not intended to limit the present invention. Those skilled in the art can change the technical features of the present invention according to the explicit or implicit contents of the present invention. All such changes may belong to the scope of patent protection sought by the present invention. In other words, the scope of patent protection of the present invention shall be determined by the scope of the patent application in this specification.

100: User Equipment 110: Wireless signal transceiver circuit 120: Computational Circuits 130: Memory S410~S495, S452~S456, S472~S476, S810~S840, S1110~S1140, S1210~S1230, S1310~S1360, S1400~S1460: Steps

FIG. 1 is a schematic diagram of downlink scheduling of conventional NB-IoT; FIG. 2 is a functional block diagram of an embodiment of a UE of NB-IoT according to the present invention; FIG. 3 is a flowchart of an embodiment of a scheduling method for a UE of the present invention; FIG. 4 is a detailed flow chart of step S450 of FIG. 3; FIG. 5 is a detailed flow chart of step S470 of FIG. 3; FIG. 6 is a flowchart of another embodiment of a scheduling method for a UE of the present invention; FIG. 7 is another schematic diagram of downlink scheduling of the conventional NB-IoT; FIG. 8 is a flowchart of a method for establishing a schedule list according to the present invention; FIG. 9 is the operation details of step S450 of FIG. 3 based on the second-order list; FIG. 10 is the operation details of step S480 of FIG. 3 based on the second-order list; FIG. 11 is a partial operation detail of step S470 of FIG. 3 based on the second-order list; Figure 12 shows the structural representation of the list of Table 3 in C language; Figure 13 shows the structural representation in C of the manifest of Table 4; and Figure 14 shows an example of index i and four functions implemented in C language.

100: User Equipment

110: Wireless signal transceiver circuit

120: Computational Circuits

130: Memory

Claims (11)

A user equipment operates on a narrowband Internet of Things (NBIoT), the user equipment includes: a memory storing a code, the code being related to the functions of the user equipment; a computing circuit, coupled to The memory is used to execute the code stored in the memory to execute the function of the user equipment; a wireless signal transceiving circuit is coupled to the computing circuit; wherein, the computing circuit transmits and receives through the wireless signal The circuit receives a signal sent by a base station and is synchronized with the base station, and receives at least one system information parameter from the base station, wherein the at least one system information parameter includes a narrowband physical downlink control channel (Narrowband Physical Downlink Control Channel) search a maximum repetition number, a period and an offset of the space; and wherein the calculating circuit creates a scheduling list according to the at least one system information parameter. The user equipment according to claim 1, wherein the schedule list directly or indirectly records a plurality of available subframes, and each available subframe is marked with an index. The user equipment according to claim 1, wherein the at least one system information parameter further includes at least one system information type and a narrowband system information block type. A user equipment operates on a narrowband Internet of Things (NBIoT), the user equipment includes: a memory storing a code, the code is related to the function of the user equipment; A computing circuit, coupled to the memory, is used to execute the program code stored in the memory to execute the function of the user equipment; a wireless signal transceiving circuit is coupled to the computing circuit; wherein, the computing The circuit receives a signal sent by a base station through the wireless signal transceiver circuit and is synchronized with the base station, and receives at least one system information parameter from the base station, wherein the at least one system information parameter includes a narrowband physical downlink control channel (Narrowband physical downlink control channel). Physical Downlink Control Channel) search space with a maximum number of repetitions, a period and an offset; and wherein the calculation circuit creates a schedule list according to the at least one system information parameter, and the schedule list directly or indirectly records plural numbers available subframes, each available subframe is marked with an index, and the calculation circuit calculates a target narrowband physical downlink control channel group according to the number of a target subframe, the period and the offset The number of a starting subframe. The user equipment according to claim 4, wherein the calculation circuit uses the number of the starting subframe to find a starting index corresponding to the starting subframe in the scheduling list, and A target index corresponding to the target subframe is found in the schedule list. The user equipment of claim 5, wherein the calculation circuit determines whether the target subframe is in the target narrowband physical downlink according to the start index, the target index and the maximum number of repetitions Controls the range covered by the channel group. The user equipment according to claim 6, wherein the calculation circuit determines whether the target subframe is a NBPCCH candidate subframe according to the target index and the number of the target subframe frame. The user equipment of claim 7, wherein the calculation circuit determines whether to receive the target subframe according to whether the target subframe is a NBPCCH candidate subframe. The user equipment as described in claim 6, wherein the start subframe is a first start subframe, and the calculation circuit finds the first start subframe of the target narrowband physical downlink control channel group starting a subframe, or finding a second starting subframe of a NBPCCH group at a time; wherein the next NBDCCH group is immediately following the target NBPDC channel Control channel groups. A user equipment operates on a narrowband Internet of Things (NBIoT), the user equipment includes: a memory storing a code, the code being related to the functions of the user equipment; a computing circuit, coupled to The memory is used to execute the code stored in the memory to execute the function of the user equipment; a wireless signal transceiving circuit is coupled to the computing circuit; wherein, the computing circuit transmits and receives through the wireless signal The circuit receives a signal sent by a base station and synchronizes with the base station, and receives at least one system information parameter from the base station, wherein the at least one system information parameter includes a narrowband physical downlink control channel (Narrowband Physical Downlink Control Channel) a maximum number of repetitions, a period and an offset of the search space; and wherein, the computing circuit creates a scheduling list according to the at least one system information parameter, and the at least one system information parameter updates Including at least one system message type and a narrowband system information block type; wherein, the calculation circuit creates a plurality of sub-lists according to the distribution of the at least one system message type and the narrowband system information block type, wherein each element of the sub-lists represents an available sub-frame; wherein the calculation circuit assigns a sub-list code for each sub-list, and calculates an element number for each sub-list. The user equipment according to claim 10, wherein the schedule list has a plurality of element groups, and each element group includes the sub-list code and an accumulated value, and the accumulated value is the number of the elements. Grand total.

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