A method, a terminal, and a base station for obtaining system information in an NR system

Abstract

The present invention provides a method, a terminal, and a base station for obtaining system information in an NR system, which determine an access opportunity of a physical random access channel closest to the current time point and use it as a first time point; determine an end time point of a random access response window corresponding to the first time point as a second time point according to a time span of this random access process from the access opportunity of the physical random access channel to an end frame of the corresponding random access response window; determine a first system information that needs to be obtained and appears after the second time point as a first system information; and send a first message including a random access preamble of the first system information to the base station at the first time point. This effectively shortens the reception duration of unnecessary system information.

Description

Technical Field

[0001] The present invention relates to the field of communication technologies, and in particular, to a method for obtaining system information, a terminal, and a base station in an NR system. Background Art

[0002] Therefore, when designing a new wireless communication system such as the 5th Generation (5G) New Radio (NR) system, the system information can be divided into necessary system information and non-necessary system information. For the necessary system information, such as the system information containing access information, etc., it can be sent by the base station through the traditional broadcast method; for the non-necessary system information, that is, the system information configured as notBroadcasting, in order to save power consumption, the base station does not always perform broadcast transmission. The base station only performs system information distribution when it receives a request from the UE to read non-necessary system information. In NR, the base station periodically distributes system information, and the UE calculates the time position of the system information distribution according to the current time point and receives the system information at the corresponding time. In general cases, for example, if the notBroadcasting system messages SI-1 and SI-2 are configured in SIB1, then MSG1 (the first message) containing Preamble index X (random access preamble index X) is first sent. After successfully receiving the random access response MSG2 (the second message), the UE receives SI-1, and then the UE continues to send MSG1 containing Preamble index Y (random access preamble index Y), then receives MSG2, and then receives SI-2, and the process is as Figure 1 shown. Compared with the MSG1 / MSG2 / MSG3 / MSG4 process in a general competitive random access process, the random access process for requesting the base station to broadcast system messages only includes two stages, MSG1 and MSG2. After the UE sends MSG1, it detects MSG2 within the ra-Respons Window (i.e., the RAR window, RAR window, or random access response window). If the RAPID (random access preamble identifier, Random Access Preamble Identifier) in the detected MSG2 is consistent with the preamble index (random access preamble index) sent by the UE, it is considered that the base station has received the request from the UE to broadcast system messages, and subsequently, the base station distributes system messages at the system message time point configured by it, as Figure 2 shown. However, if following the existing system message acquisition process, as Figure 3In the scenario shown, the UE will miss the opportunity to receive the most recent notBroadcasting system message. Since the position where the notBroadcastting system information appears is not judged, the MSG1 of the SI 1 request is sent first. However, when the MSG2 response is received, the transmission window of SI 1 has already been missed, and it needs to be postponed to the transmission window of SI 1 in the next cycle for reception. If the SI 2 request is sent again, the transmission window of SI 2 may also be missed, and it can only be obtained in the next cycle, resulting in an extended system information acquisition time. Different SI cycles may be configured differently, resulting in a longer acquisition time when the terminal needs to obtain multiple system information. Summary of the Invention

[0003] Based on the problems in the prior art, the present invention provides a method, a terminal, and a base station for acquiring system information in an NR system, aiming to solve the technical problems such as the long acquisition time of non-essential system information in the prior art.

[0004] A method for acquiring system information in an NR system includes:

[0005] Step A1, determining the access opportunity of the physical random access channel closest to the current time point and using it as the first time point;

[0006] Step A2, determining the end time point of the random access response window corresponding to the first time point according to the time span of this random access process from the access opportunity of the physical random access channel to the end frame of the corresponding random access response window, and using it as the second time point;

[0007] Step A3, determining the first system information that needs to be acquired and appears after the second time point, and using it as the first system information;

[0008] Step A4, sending a first message containing a random access preamble of the first system information to the base station at the first time point.

[0009] Further, the time span of the random access process refers to the sum of the time interval from the access opportunity of the physical random access channel to the corresponding random access response window and the window length of the random access response window.

[0010] Further, after step A4, it further includes:

[0011] Step A5, receiving the first system information from the base station within the transmission window corresponding to the first system information.

[0012] Further, after step A3, it further includes:

[0013] Step B1, determining the time point of the start frame of the transmission window corresponding to the first system information and using it as the third time point;

[0014] Step B2: Determine the number of times the random access procedure can be completed between the second time point and the third time point according to the time span of the random access procedure:

[0015] If the number of times is 0, execute Step A4;

[0016] If the number of times is not 0, execute Step B3;

[0017] Step B3: Determine several system information that appears earlier in chronological order after the first system information, and use it as the second system information. The number of the second system information is equal to the number of times, and then execute Step A4;

[0018] In Step A4:

[0019] If the number of times is 0, send a first message containing a random access preamble of the first system information to the base station at the first time point;

[0020] If the number of times is not 0, before the third time point, according to the chronological order of the appearance of the first system information and the second system information, send a first message containing a random access preamble of one of the first system information and the second system information to the base station at the access opportunity of each physical random access channel.

[0021] Further, Step A5 includes:

[0022] If the number of times is 0, receive the first system information within the transmission window corresponding to the first system information;

[0023] If the number of times is not 0, receive the first system information within the transmission window corresponding to the first system information, and sequentially receive the second system information within the transmission window corresponding to the second system information.

[0024] Further, after Step A4, it further includes:

[0025] Step A04: Receive a second message within the random access response window corresponding to the first time point. The second message includes a random access preamble identifier generated by the base station according to the random access preamble in the first message;

[0026] Step A5: Receive the first system information from the base station within the transmission window corresponding to the first system information;

[0027] After the end of the random access response window in Step A04, it further includes:

[0028] Step C1: Determine the time point of the start frame of the transmission window corresponding to the first system information, and use it as the third time point;

[0029] Step C2: Determine the number of random access procedures that can be completed before the third time point according to the time span of the random access procedure:

[0030] If the number is 0, execute step A5;

[0031] If the number is not 0, execute step C3;

[0032] Step C3: Determine several system information that need to be obtained and appear earlier in chronological order after the first system information, and use them as the second system information. The number of the second system information is equal to the number;

[0033] Step C4: Before the third time point, according to the chronological order of the appearance of the second system information, at the access opportunity of each physical random access channel, send a first message containing a random access preamble of a second system information to the base station, and then execute step A5;

[0034] Step A5 includes:

[0035] If the number is 0, receive the first system information within the transmission window corresponding to the first system information;

[0036] If the number is not 0, receive the first system information within the transmission window of the first system information, and sequentially receive the second system information within the transmission window corresponding to the second system information.

[0037] A terminal for implementing a method for obtaining system information in an NR system, including a processor, and the processor is used for:

[0038] Determine the access opportunity of the physical random access channel closest to the current time point, and use it as the first time point;

[0039] According to the time span of this random access procedure from the access opportunity of the physical random access channel to the end frame of the corresponding random access response window, determine the end time point of the random access response window corresponding to the first time point, and use it as the second time point;

[0040] Determine the first system information that needs to be obtained and appears after the second time point, and use it as the first system information;

[0041] Send a first message containing a random access preamble of the first system information to the base station at the first time point.

[0042] Further, the processor is further used to execute after sending the first message at the first time point:

[0043] Receive the first system information from the base station within the transmission window corresponding to the first system information.

[0044] Further, the processor is further configured to perform the following after determining the first system information:

[0045] Determine the time point of the start frame of the transmission window corresponding to the first system information, and use it as the third time point;

[0046] According to the time span of the random access process, determine the number of times the random access process can be completed between the second time point and the third time point:

[0047] If the number of times is 0, send a first message containing a random access preamble of the first system information to the base station at the first time point;

[0048] If the number of times is not 0, then determine several system information that need to be obtained and are earlier in time sequence after the first system information, and use it as the second system information. The number of the second system information is equal to the number of times. Subsequently, before the third time point, according to the time sequence of the appearance of the first system information and the second system information, send a first message containing a random access preamble of one of the first system information and the second system information to the base station at the access opportunity of each physical random access channel.

[0049] A base station, connected to the terminal as described above, includes:

[0050] Receive the first message sent by the terminal and containing a random access preamble;

[0051] Generate a second message containing a random access preamble identifier according to the random access preamble in the first message;

[0052] Send the second message to the terminal;

[0053] Send system information to the terminal in the transmission window of the system information.

[0054] The beneficial technical effect of the present invention is to determine the physical random access channel opportunity closest to the current time point and the time point until the random access response ends, and find the earliest available system information to receive the system information when the transmission window of the system information arrives, thereby shortening the receiving duration of the system information. Description of the Drawings

[0055] Figures 1-3 It is an explanatory diagram of the acquisition process of non-essential system information in the prior art;

[0056] Figure 4 It is a step flow chart of a method for acquiring system information in an NR system according to the present invention;

[0057] Figures 5-7 It is a timing diagram of using a method for acquiring system information in an NR system according to the present invention;

[0058] Figure 8 It is a flowchart of the steps of a preferred real-time manner for a method of obtaining system information in an NR system according to the present invention;

[0059] Figure 9 It is a timing diagram of a preferred real-time manner for a method of obtaining system information in an NR system according to the present invention;

[0060] Figure 10 It is a flowchart of the steps of another preferred real-time manner for a method of obtaining system information in an NR system according to the present invention. Specific embodiments

[0061] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0062] It should be noted that, without conflict, the embodiments in the present invention and the features in the embodiments can be combined with each other.

[0063] Next, the present invention will be further described in conjunction with the accompanying drawings and specific embodiments, but it is not a limitation of the present invention.

[0064] See Figure 4 , the present invention relates to a method of obtaining system information in an NR system, including:

[0065] Step A1, determining the access opportunity of the physical random access channel closest to the current time point and using it as the first time point;

[0066] Step A2, determining the end time point of the random access response window corresponding to the first time point as the second time point according to the time span of this random access process from the access opportunity of the physical random access channel to the end frame of the corresponding random access response window;

[0067] Step A3, determining the first system information that needs to be obtained and appearing after the second time point and using it as the first system information;

[0068] Step A4, sending a first message including a random access preamble containing the first system information to the base station at the first time point.

[0069] After sending the first message in step A4, receiving a second message including a random access preamble identifier within the corresponding random access response window.

[0070] Furthermore, the time span of the random access process refers to the sum of the time interval from the access opportunity of the physical random access channel to the corresponding random access response window and the window length of the random access response window.

[0071] Specifically, before step A1, it further includes:

[0072] Step A01, obtaining the configuration information of the physical random access channel.

[0073] In step A1, determine the access opportunity of the physical random access channel closest to the current time point according to the configuration information of the physical random access channel;

[0074] In step A2, determine the time span of the random access process according to the configuration information of the physical random access channel.

[0075] The access opportunity PRACH Occasion of the physical random access channel is generally configured periodically;

[0076] After sending the first message MSG1, the terminal receives the corresponding second message MSG2 within a configured random access response window, i.e., the RAR window. The second message MSG2 includes the random access preamble identifier generated by the base station according to the random access preamble in the first message.

[0077] The system information SI appears periodically within a fixed-length window configured by a base station, i.e., the transmission window of the system information (SI transmission window).

[0078] Therefore, after the terminal receives the configuration information of the physical random access channel, according to the current time point, it calculates the access opportunity PRACH Occasion of the nearest physical random access channel, determines the time point when the first message can be accessed recently, i.e., the first time point. The first time point plus the time interval from the random access response window, and then plus the window length of the random access response window, obtains the end time point of the random access response window, i.e., the second time point. According to the second time point and the transmission period of the system information configured by the system, it knows the first system information that appears after the second time point, and includes the random access preamble preamble of this system information in the first message for transmission, so as to obtain the system information when the system information is sent. Compared with the prior art, sending MGS1 according to the order of the system information sent within the period may miss the system information and cause the acquisition time of the system information to be extended. The present invention shortens the acquisition time of the system information.

[0079] Reference Figure 5As shown, according to the acquisition method of the present invention, it is known that the latest system information after the second time point is SI1. Therefore, a first message MSG1 containing the random access preamble of SI1 is sent. If the second message MSG2 is received within the MSG2 window, SI1 can be received within the RAR window of SI1 at the SI1 delivery time point.

[0080] Reference Figure 6 As shown, according to the acquisition method of the present invention, it is known that the latest system information after the second time point is SI2. Therefore, a first message MSG1 containing the random access preamble of SI2 is sent. If the second message MSG2 is received within the MSG2 window, SI2 can be received within the RAR window of SI2 at the SI2 delivery time point.

[0081] Reference Figure 7 As shown, according to the acquisition method of the present invention, it is known that the latest system information after the second time point is SI3. Therefore, a first message MSG1 containing the random access preamble of SI3 is sent. If the second message MSG2 is received within the MSG2 window, SI3 can be received within the RAR window of SI3 at the SI3 delivery time point.

[0082] Furthermore, the system information is non-essential system information, that is, the system information configured with notBroadcasting in SIB1.

[0083] The configuration of the physical random access channel PRACH includes SIB1, and information related to the system message is configured in SIB1. The terminal can select the system message to be acquired according to the configured system message.

[0084] According to the configuration information of the physical random access channel PRACH, obtain the physical random access channel occasion PRACHOccasion, the time interval between the physical random access channel occasion PRACH Occasion and the random access response window RAR window, the window length of the random access response window RAR window, and the delivery time point of the system information SI to be acquired.

[0085] Furthermore, after step A4, it further includes:

[0086] Step A5, receiving the first system information from the base station within the transmission window corresponding to the first system information.

[0087] See Figure 8 Furthermore, after step A3, it further includes:

[0088] Step B1, determine the time point of the starting frame of the transmission window corresponding to the first system information, and use it as the third time point;

[0089] Step B2, according to the time span of the random access process, determine the number of times the random access process can be completed between the second time point and the third time point:

[0090] If the number of times is 0, execute Step A4;

[0091] If the number of times is not 0, execute Step B3;

[0092] Step B3, determine the several system information that appears earlier in chronological order after the first system information, and use it as the second system information. The number of the second system information is equal to the number of times, and then execute Step A4;

[0093] In Step A4:

[0094] If the number of times is 0, then send a first message containing the random access preamble of the first system information to the base station at the first time point;

[0095] If the number of times is not 0, before the third time point, according to the chronological order of the appearance of the first system information and the second system information, send a first message containing a random access preamble of one of the first system information and the second system information to the base station at the access opportunity of each physical random access channel.

[0096] After each sending of the first message, receive a second message containing the random access preamble identifier within the corresponding random access response window.

[0097] Further, Step A5 includes:

[0098] If the number of times is 0, then receive the first system information within the transmission window corresponding to the first system information;

[0099] If the number of times is not 0, then receive the first system information within the transmission window corresponding to the first system information, and sequentially receive the second system information within the transmission window corresponding to the second system information.

[0100] Participate Figure 9, according to the current time point, after MSG1 / MSG2 of SI 1, a random access procedure of MSG1 / MSG2 can also be performed before the transmission window of SI 1 arrives. If the terminal needs to obtain messages SI 2 and SI 3, since the number of times is only once, and the transmission window of SI 2 is after the transmission window of SI1 and closer to the transmission window of SI 1, therefore, before the transmission window of SI 1, during the MSG1 / MSG2 process of SI2, SI 1 can be received when the transmission window of SI 1 arrives, and SI 2 can be received when SI2 arrives.

[0101] Specifically, in step B2, since the physical random access channel occasion (PRACH Occasion) is configured periodically, the time interval between PRACH Occasion and the RAR window is fixed, and the length of the RAR window is fixed. Therefore, it is easy to obtain the number of times allowed for the random access procedure.

[0102] In the present invention, when the terminal UE needs to receive notBroadcasting system information, it refers to the configuration information of the PRACH, including PRACH Occasion, the length of the MSG2 reception window (i.e., the RAR window), the transmission time point of the notBroadcasting system information, and the configuration of the notBroadcasting system information, obtains the location of the notBroadcasting system information, and selects a preamble corresponding to the nearest readable notBroadcasting SI to send to the base station, thereby shortening the time for the UE to receive the system information.

[0103] Specifically, the transmission window lengths of each system information are the same.

[0104] Specifically, the transmission periods of each system information are different.

[0105] See Figure 10 , as a preferred real-time manner, after step A4, it further includes:

[0106] Step A04, receiving a second message within the random access response window corresponding to the first time point, where the second message includes a random access preamble identifier generated by the base station according to the random access preamble in the first message;

[0107] Step A5, receiving the first system information from the base station within the transmission window corresponding to the first system information;

[0108] After the random access response window in step A04 ends, it further includes:

[0109] Step C1: Determine the time point of the start frame of the transmission window corresponding to the first system information, and use it as the third time point;

[0110] Step C2: According to the time span of the random access process, determine the number of times the random access process can be completed before the third time point:

[0111] If the number of times is 0, execute Step A5;

[0112] If the number of times is not 0, execute Step C3;

[0113] Step C3: Determine several system information that need to be obtained and appear earlier in chronological order after the first system information, and use it as the second system information. The number of the second system information is equal to the number of times;

[0114] Step C4: Before the third time point, according to the chronological order of the appearance of the second system information, at the access opportunity of each physical random access channel, send a first message containing a random access preamble of a second system information to the base station, and then execute Step A5;

[0115] Step A5 includes:

[0116] If the number of times is 0, then receive the first system information within the transmission window corresponding to the first system information;

[0117] If the number of times is not 0, then receive the first system information within the transmission window of the first system information, and sequentially receive the second system information within the transmission window corresponding to the second system information.

[0118] The present invention also provides a terminal for executing the foregoing method for obtaining system information in an NR system, including a processor, and the processor is used for:

[0119] Determine the access opportunity of the physical random access channel closest to the current time point, and use it as the first time point;

[0120] According to the time span of this random access process from the access opportunity of the physical random access channel to the end frame of the corresponding random access response window, determine the end time point of the random access response window corresponding to the first time point, and use it as the second time point;

[0121] Determine the first system information that appears after the second time point, and use it as the first system information;

[0122] Send a first message containing a random access preamble of the first system information to the base station at the first time point.

[0123] Further, the processor is further used to execute after sending the first message at the first time point:

[0124] Receive the first system information from the base station within the transmission window corresponding to the first system information.

[0125] Furthermore,

[0126] The processor is further configured to execute after determining the first system information:

[0127] Determine the time point of the start frame of the transmission window corresponding to the first system information, and use it as the third time point;

[0128] According to the time span of the random access process, determine the number of times the random access process can be completed between the second time point and the third time point:

[0129] If the number of times is 0, send a first message including a random access preamble containing the first system information to the base station at the first time point;

[0130] If the number of times is not 0, then determine the several system information that appears earlier in chronological order after the first system information, and use it as the second system information. The number of the second system information is equal to the number of times. Subsequently, before the third time point, according to the chronological order of the appearance of the first system information and the second system information, send a first message including a random access preamble containing one of the first system information and the second system information to the base station at the access opportunity of each physical random access channel.

[0131] The present invention also provides a base station, connected to the aforementioned terminal, including:

[0132] Receive the first message including a random access preamble sent by the terminal;

[0133] Generate a second message including a random access preamble identifier according to the random access preamble in the first message;

[0134] Send the second message to the terminal;

[0135] Send system information to the terminal within the transmission window of the system information.

[0136] The above are only preferred embodiments of the present invention, and do not limit the implementation manners and protection scope of the present invention. For those skilled in the art, it should be able to realize that all equivalent replacements and obvious changes made by using the description and illustrations of the present invention should be included in the protection scope of the present invention.

Claims

1. A method for obtaining system information in an NR system, characterized in that, Including: Step A1: Determine the access opportunity of the physical random access channel closest to the current time point and use it as the first time point; Step A2: Determine the end time point of the random access response window corresponding to the first time point according to the time span of this random access process from the access opportunity of the physical random access channel to the end frame of the corresponding random access response window, and use it as the second time point; Step A3: Determine the first system information that needs to be obtained and appears after the second time point, and use it as the first system information; Step A4: Send a first message containing the random access preamble of the first system information to the base station at the first time point.

2. The method for obtaining system information in an NR system according to claim 1, wherein The time span of the random access process refers to the sum of the time interval from the access opportunity of the physical random access channel to the corresponding random access response window and the window length of the random access response window.

3. The method for obtaining system information in an NR system according to claim 1, characterized in that, After step A4, it further includes: Step A5: Receive the first system information from the base station within the transmission window corresponding to the first system information.

4. The method for obtaining system information in an NR system according to claim 3, wherein After step A3, it further includes: Step B1: Determine the time point of the start frame of the transmission window corresponding to the first system information and use it as the third time point; Step B2: Determine the number of times the random access process can be completed between the second time point and the third time point according to the time span of the random access process: If the number of times is 0, execute step A4; If the number of times is not 0, execute step B3; Step B3: Determine the several system information that needs to be obtained and appears earlier in chronological order after the first system information, and use it as the second system information. The number of the second system information is equal to the number of times, and then execute step A4; In step A4: If the number of times is 0, then send a first message containing the random access preamble of the first system information to the base station at the first time point; If the number of times is not 0, before the third time point, according to the chronological order of the appearance of the first system information and the second system information, send a first message containing one of the first system information and the second system information in the random access preamble to the base station at the access opportunity of each physical random access channel.

5. The method for obtaining system information in an NR system according to claim 4, characterized in that, Step A5 includes: If the number of times is 0, then receive the first system information within the transmission window corresponding to the first system information; If the number of times is not 0, then receive the first system information within the transmission window corresponding to the first system information, and sequentially receive the second system information within the transmission window corresponding to the second system information.

6. The method for obtaining system information in an NR system according to claim 1, characterized in that, After step A4, it further includes: Step A04: Receive a second message within the random access response window corresponding to the first time point. The second message includes the random access preamble identifier generated by the base station according to the random access preamble in the first message; Step A5: Receive the first system information from the base station within the transmission window corresponding to the first system information; After the end of the random access response window in step A04, the following steps are further included: Step C1, determining the time point of the start frame of the transmission window corresponding to the first system information and using it as the third time point; Step C2, determining the number of times the random access process can be completed before the third time point according to the time span of the random access process: If the number is 0, execute step A5; If the number is not 0, execute step C3; Step C3, determining several system information that need to be obtained and that appear earlier in chronological order after the first system information and using it as the second system information, the number of the second system information being equal to the number; Step C4, before the third time point, according to the chronological order of the appearance of the second system information, sending a first message including a random access preamble of one piece of the second system information to the base station at the access opportunity of each physical random access channel, and then executing step A5; Step A5 includes: If the number is 0, receiving the first system information within the transmission window corresponding to the first system information; If the number is not 0, receiving the first system information within the transmission window of the first system information, and successively receiving the second system information within the transmission window corresponding to the second system information.

7. A terminal, characterized in that, A method for obtaining system information in an NR system as claimed in any one of claims 1-6, comprising a processor, wherein the processor is configured to: Determine the access opportunity of the physical random access channel closest to the current time point and use it as the first time point; Determine the end time point of the random access response window corresponding to the first time point according to the time span of the random access process from the access opportunity of the physical random access channel to the end frame of the corresponding random access response window, and use it as the second time point; Determine the first system information that is the first to appear after the second time point and use it as the first system information; Sending a first message including a random access preamble of the first system information to the base station at the first time point.

8. A terminal according to claim 7, characterized in that, The processor is further configured to execute after sending the first message at the first time point: Receiving the first system information from the base station within the transmission window corresponding to the first system information.

9. The terminal according to claim 8, wherein The processor is further configured to execute after determining the first system information: Determine the time point of the start frame of the transmission window corresponding to the first system information and use it as the third time point; Determine the number of times the random access process can be completed between the second time point and the third time point according to the time span of the random access process: If the number is 0, sending a first message including a random access preamble of the first system information to the base station at the first time point; If the number is not 0, determine several pieces of the system information that need to be obtained and appear earlier in chronological order after the first system information, and use them as the second system information. The number of the second system information is equal to the number. Subsequently, before the third time point, according to the chronological order of the appearance of the first system information and the second system information, send a first message including a random access preamble of one piece of the system information among the first system information and the second system information at the access opportunity of each physical random access channel to the base station.

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