KR20220169893A - Method and apparatus for transmitting and receiving characteristic information of gnss subframe - Google Patents

Abstract

A method and device for transmitting and receiving GNSS subframe characteristic information are disclosed. The method for transmitting and receiving GNSS subframe characteristic information is a method of a first device. The method may include the steps of: receiving a subframe including first information which is characteristic information of a subframe from a second device; checking the format of the subframe based on the first information; and determining whether to decode data included in the subframe based on the checked format of the subframe.

Description

Method and device for transmitting and receiving characteristic information of GNSS subframe

The present invention relates to a method and/or apparatus for transmitting and receiving characteristic information, and more particularly, to a method and/or apparatus for transmitting and receiving characteristic information of a Global Navigation Satellite System (GNSS) subframe.

Indian regional navigation satellite system (IRNSS) in India (or navigation with Indian constellation (NavIC)), global navigation satellite system (GPS) in the United States, global navigation satellite system (GLONASS) in Russia, Galileo in Europe, etc. A global navigation satellite system (GNSS) is a system for receiving information about a satellite's location, time, and other correction factors from a satellite to measure accurate time information and location.

Meanwhile, in a satellite navigation system, a receiver may acquire subframe synchronization, receive subframes, perform decoding, and then acquire information transmitted by each subframe. At this time, even if the subframe includes data that the terminal cannot use or does not need, the receiver receives and/or decodes the above-described subframe and examines the information of each item to determine whether the corresponding subframe is required by the receiver. There is a problem that can be judged.

An object of the present invention to solve the above problem is to provide a method and/or apparatus for transmitting and receiving GNSS (Global Navigation Satellite System) subframe characteristic information.

To achieve the above object, a method for transmitting and receiving GNSS (global navigation satellite system) subframe characteristic information according to a first embodiment of the present application is a method of a first device, from a second device Receiving a subframe including first information that is characteristic information of the subframe; Checking a characteristic or format of the subframe based on the first information; and determining whether to decode data included in the subframe based on the checked characteristics or format of the subframe.

Here, the first information may be indicated by a sync word included in the subframe.

Here, when it is determined to perform decoding of the data, the decoding operation of the data is performed based on the coding rate information used for channel coding of the data indicated by the first information. It may further include steps to perform.

Here, before the step of determining whether to decode, determining whether to receive the data included in the subframe based on the first information and determining not to receive the data included in the subframe In addition, the step of operating in a sleep mode (slip mode) for a preset period of time may be further included.

Here, when a mapping relationship between the number of the subframe and the first information is set in advance, the number of the subframe may be identified based on the sync word.

Here, when a mapping relationship between the accuracy of the subframe and the first information is set in advance, the accuracy of the subframe is checked based on the sync word, and the accuracy is included in the subframe. It may be the accuracy of the navigation information indicated by the data obtained.

Here, when a mapping relationship between whether channel coding of the subframe is used and the first information is preset, whether channel coding of the subframe is used is confirmed based on the sync word. can do.

Here, when the subframe includes a sync word, a subframe characteristic indicator, and the data, the first information may be indicated by the subframe characteristic indicator.

Here, when a mapping relationship between each of the number and accuracy of the subframe and the first information is set in advance, each of the number and accuracy of the subframe is confirmed by the subframe characteristic indicator, and the accuracy is determined by the subframe number and accuracy. It may be the accuracy of navigation information indicated by the data included in .

Here, when a mapping relationship between the accuracy of the subframe and the first information is preset, the accuracy of the subframe may be confirmed based on the subframe characteristic indicator.

A method for transmitting and receiving GNSS (global navigation satellite system) subframe characteristic information according to a second embodiment of the present application for achieving the above object is a method of a second device, comprising: generating data having a first characteristic; generating first information indicating the first characteristic; generating a subframe including a field associated with the first information and the data; and transmitting the subframe, wherein the first information may be used to determine whether to decode the data included in the subframe.

Here, the field may be a sync word, and a mapping relationship between the first information and the sync word may be preset.

Here, the first information is characterized in that it indicates coding rate information used for channel coding of the data, and the code rate information is used to decode the data. can

Here, when a mapping relationship between each of the number and accuracy of the subframe and the first information is preset, each of the number and accuracy of the subframe is confirmed by the sync word, and the accuracy is included in the subframe. It may be the accuracy of the navigation information indicated by the data obtained.

Here, when a mapping relationship between whether channel coding is used in the subframe and the first information is preset, the sync word indicates whether channel coding is used in the subframe. there is.

To achieve the above object, an apparatus for transmitting and receiving GNSS (global navigation satellite system) subframe characteristic information according to a third embodiment of the present application is a first apparatus, and includes: a processor; a memory that communicates electronically with the processor; and instructions stored in the memory; When the instructions are executed by the processor, the instructions cause the first device to receive a subframe including first information that is characteristic information of the subframe from the second device; Checking the characteristics or format of the subframe based on the first information; And based on the identified characteristics or format of the subframe, it may operate to determine whether to decode data included in the subframe.

Here, the first information may be indicated by a sync word included in the subframe.

Here, the first information may be indicated by a subframe characteristic indicator included in the subframe, which is a subframe characteristic indicator.

According to the present application, a receiver can determine the characteristics of a subframe to determine state information, data content type and/or change of data of a corresponding subframe, and the receiver determines the purpose of the receiver or the corresponding subframe based on the characteristics of the subframe. It is possible to perform a reception and / or decoding operation suitable for.

In addition, according to the present application, the satellite navigation system can configure subframes and transmit/receive channels adaptively, the receiver can save power required for unnecessary data reception by avoiding unnecessary reception operations, and the receiver has a low error rate. A navigation solution can be derived quickly.

1 is a conceptual diagram illustrating a first embodiment of a structure of a master frame of navigation with Indian constellation (NavIC) (or Indian regional navigation satellite system (IRNSS)).
2 is a conceptual diagram illustrating a first embodiment of a structure of a subframe of NavIC.
3 is a conceptual diagram illustrating a first embodiment of a structure of subframe 1 or subframe 2 before forward error correction (FEC) encoding and sync word insertion.
4 is a conceptual diagram illustrating a first embodiment of a structure of subframe 3 or subframe 4 before FEC encoding and sync word insertion.
5 is a flowchart illustrating a first embodiment of a method for transmitting GNSS (global navigation satellite system) subframe characteristic information.
6 is a flowchart illustrating a first embodiment of a method for receiving GNSS subframe characteristic information.
7 is a conceptual diagram illustrating a first embodiment of a structure of a subframe including a 'subframe characteristic indicator'.
8 is a conceptual diagram illustrating a second embodiment of a structure of a subframe including a 'subframe characteristic indicator'.

A communication system to which embodiments according to the present application are applied will be described. Communication systems to which embodiments according to the present application are applied are not limited to those described below, and embodiments according to the present application may be applied to various communication systems. Here, the communication system may be used in the same sense as a communication network.

Since the present application can make various changes and have various embodiments, specific embodiments are illustrated in the drawings and described in detail. However, this is not intended to limit the present application to specific embodiments, and should be understood to include all modifications, equivalents, and substitutes included in the spirit and scope of the present application.

Terms such as first and second may be used to describe various components, but the components should not be limited by the terms. These terms are only used for the purpose of distinguishing one component from another. For example, a first element may be termed a second element, and similarly, a second element may be termed a first element, without departing from the scope of the present application. The term "and/or" includes any combination of a plurality of related listed items or any of a plurality of related listed items.

It is understood that when an element is referred to as being "connected" or "connected" to another element, it may be directly connected or connected to the other element, but other elements may exist in the middle. It should be. On the other hand, when an element is referred to as “directly connected” or “directly connected” to another element, it should be understood that no other element exists in the middle.

Terms used in this application are only used to describe specific embodiments, and are not intended to limit the present application. Singular expressions include plural expressions unless the context clearly dictates otherwise. In this application, the terms "include" or "have" are intended to designate that there is a feature, number, step, operation, component, part, or combination thereof described in the specification, but one or more other features It should be understood that the presence or addition of numbers, steps, operations, components, parts, or combinations thereof is not precluded.

1 is a conceptual diagram illustrating a first embodiment of a master frame structure of Navigation Indian Constellation (NavIC).

Referring to FIG. 1, a data frame for message delivery for SPS (Standard Positioning Service) of NavIC (or Indian Regional Navigation Satellite System (IRNSS)), India's GNSS (Global Navigation Satellite System) ) structure may be as follows: A master frame of NavIC may consist of four subframes, and each subframe of NavIC may consist of 600 symbols Master frame of NavIC (master frame) may consist of 2400 symbols.

2 is a conceptual diagram illustrating a first embodiment of a subframe structure of NaviIC.

Referring to FIG. 2, a subframe of NavIC may consist of 600 symbols. A subframe of NaviIC may include a sync (synchronization) code (or preamble) and/or navigation data (or NAV data) for subframe synchronization. The sync code may include a sync word, and the sync word may consist of the first 16 bits of the NavIC subframe. Forward Error Correction (FEC) encoding may not be used for the sync word. In addition, EB90 Hex may be used as a sync pattern for subframe synchronization of NaviIC. Navigation data (or NAV data) carried after the sync code of the subframe of NaviIC may be data generated by FEC encoding 292 bits at a 1/2 code rate and interleaving the encoded bits. .

That is, the transmitter can FEC-encode 292 bits at a code rate of 1/2, and the transmitter can generate NAV data of 584 symbols by interleaving the encoded bits. The transmitter may generate an SPS signal by modulating with Binary Phase Shift Keying (BPSK) (1), and the transmitter transmits the generated SPS signal to the L5 band (1164.45 - 1188.45 MHz) and/or the S band (2483.5 - 2500 MHz). can transmit Here, the symbol transmission rate of the modulated signal may be 50 sps (symbol per second), 1/2 coding rate FEC (Forward Error Correction) may be used, and the data transmission rate may be 25 bps (bit per second) second) can be. The receiver may acquire subframe synchronization by searching for a sync pattern of the SPS signal received from the transmitter, and after obtaining synchronization, the receiver may acquire information transmitted to the subframe through FEC decoding.

NAV data may consist of 584 symbols after the sync code of the subframe of NavIC. A subframe of NavIC may be divided into subframe 1, subframe 2, subframe 3, or subframe 4. Subframe 1, subframe 2, subframe 3, or subframe 4 may be indicated by a subframe ID (or subframe number).

3 is a conceptual diagram illustrating a first embodiment of a structure of subframe 1 or subframe 2 before FEC encoding and sync code insertion.

Referring to FIG. 3, the subframe structure before FEC encoding and sync code insertion of subframe 1 or subframe 2 may be as follows. Subframe 1 or subframe 2 includes TLM (telemetry), TOWC (time of week count), alert flag, AUTONAV, subframe ID (identifier), spare, NAV data , a cyclic redundancy check (CRC) and/or a tail item. In FIG. 3 , numbers above each item may indicate data bit positions at which each item starts, and numbers below each item may indicate the number of bits of each item.

NAV data of subframe 1 and/or subframe 2 may include primary navigation parameter information. The essential navigation parameter information described above includes satellite ephemeris information, satellite clock correction parameters, user range accuracy (URA) information, total group delay information, or satellite and signal health. It may include at least one of information (satellite & signal health status).

The above-described URA may mean a statistical indication of an accuracy range related to a specific space vehicle (SV), and the URA may provide a 1 sigma estimate of the user range error of NAV data through a value of 0 to 15. there is. Table 1 below may indicate mapping between URA indexes and URA values. For example, when the URA index value is set to 'URA=15', it may indicate that the navigation accuracy prediction = 6144.00 m (meter) < URA or there is no usable accuracy prediction.

4 is a conceptual diagram illustrating a first embodiment of a structure of subframe 3 or subframe 4 before FEC encoding and sync code insertion.

Referring to FIG. 4, the subframe structure and/or content of subframe 3 or subframe 4 before FEC application may be as follows. Subframe 3 or subframe 4 may include TLM, TOWC, warning flag, AUTONAV, subframe ID, spare, message ID (message ID), NAV data, PRN ID, CRC, and/or tail items. In FIG. 4 , numbers above each item may indicate data bit positions at which each item starts, and numbers below each item may indicate the number of bits of each item.

Subframe 3 and/or subframe 4 may include secondary navigation parameter information. The above-described auxiliary navigation parameter information includes satellite almanac information, ionospheric grid delay and confidence information, IRNSS time offset information for UTC and GNSS, ionospheric delay correction constant correction coefficients, text messages, differential corrections and/or earth orientation parameters.

Subframe 3 or subframe 4 may have various message types according to the contents of data to be transmitted. Contents of data to be transmitted in subframe 3 or subframe 4 can be identified by message ID. For example, 'message type 0' may mean that the NAV data of the corresponding subframe is a null message, and 'message type 14' may mean that the NAV data of the corresponding subframe is a differential correction parameter (DC) for the satellite. (differential correction) parameters).

에서 UDRA는 'UDRA = UDRA + UD

A(

)'로 계산될 수 있다. The above-described DC parameters may provide the user with correction information to be applied to clocks and/or ephemeris data transmitted by other satellites in the AutoNav mode. DC parameters may include ephemeris differential correction and/or satellite clock differential correction (CDC) information. User Differential Range Accuracy (UDRA) included in the aforementioned DC parameters may provide navigation accuracy to which differential correction is applied. Table 2 below may indicate mapping of UDRA index values and UDRAs. For example, UDRA = -16 may indicate 'no prediction accuracy available', and a specific time

UDRA in 'UDRA = UDRA + UD

A(

)' can be calculated.

Table 3 below may indicate contents related to each item described above.

In addition, the NAV data may include a health flag (L5 flag and/or S flag), and Table 4 below may indicate a description of the health flag.

GNSSs other than NaviIC (e.g., US Global Positioning System (GPS), Russia's global navigation satellite system (GLONASS), and/or Europe's Galileo) also have a structure similar to the subframe structure of NavIC described above. Subframes can be configured.

Meanwhile, a satellite navigation system having the above-described subframe structure (or a similar subframe structure) obtains information (or data) transmitted by each subframe after performing decoding after obtaining subframe synchronization. can do. At this time, even if a subframe includes data that the terminal cannot use or does not need, in the satellite navigation system, the receiver receives and/or decodes the subframe, examines the information of each item, and selects the subframe as needed by the receiver. There may be cases in which it can be determined whether or not to do so.

Accordingly, in the satellite navigation system that transmits and receives the above-described subframes, a subframe including data that is unusable or unnecessary to a general receiver may need to be received and/or decoded. Accordingly, in the satellite navigation system, the terminal may consume power in receiving and/or decoding even a subframe including unusable or unnecessary data.

In addition, in the satellite navigation system that transmits and receives the above-described subframes, it may be difficult to explicitly deliver frame configuration information to a receiver when adaptively configuring a frame according to a channel state between a satellite and a region to be serviced. In addition, in the satellite navigation system that transmits and receives the above-described subframes, it may be difficult for the transmitter to explicitly transfer frame configuration information to the receiver and it may be difficult to configure the subframes adaptively.

In addition, in the satellite navigation system that transmits and receives the above-described subframe, even if a subframe is generally unusable due to poor data quality or low accuracy, the receiver can recognize that unnecessary information has been received after receiving and decoding the corresponding subframe. can That is, the receiver may have to receive and/or decode unnecessary subframes.

For example, even if a subframe warning flag is displayed and the receiver recognizes that the user has a risk of using navigation data of a specific satellite delivered by the subframe, even if the subframe information is not used, the receiver uses It may be necessary to receive and/or decode subframes that do not.

As another example, even if the health flag of the NAV data of subframes 1 and/or 2 is set to '1' and the NAV data is in a bad state and is not used, the receiver receives and/or decodes the corresponding subframe It can be recognized that the NAV data state is bad.

As another example, if the URA value of the NAV data of subframe 1 is 'URA=15', that is, even if the navigation accuracy prediction is 　6144.00 m < URA or there is no accuracy prediction available, the receiver does not use the data. may need to perform corresponding subframe reception and/or channel decoding.

As another example, even when the transmitter transmits an idle pattern that repeatedly transmits '0' and '1' to a subframe because there is no data to be transmitted, the receiver receives and/or decodes the subframe. After that, it can be seen that meaningless data has been received.

As another example, even when the transmitter transmits subframe 3 or subframe 4 of 'message type 0' that transmits a null message, the receiver receives and/or decodes the corresponding subframe and then transmits the subframe that it does not need. You can see that a null message was received.

As another example, if the UDRA value of the NAV data of subframe 3 or subframe 4 is 'UDRA = -16', that is, even if there is no usable prediction accuracy, the receiver may use the subframe Even if the included data is not used, an accuracy problem may be identified after receiving and/or decoding the above-described subframe.

In addition, in an existing satellite navigation system that transmits and receives the above-described subframes, a subframe including data not required by a receiver may also need to be received and/or decoded. That is, a situation may arise in which the receiver needs only information delivered in a specific subframe, and in this case, a situation may occur in which the receiver needs to receive and/or decode a subframe including unnecessary data. This is because there is a case in which it is unknown before reception and/or decoding whether a subframe including data required by the receiver is present.

For example, the receiver may require only information transmitted through subframe 1 and/or subframe 2. For example, when a receiver first seeks a navigation solution, or a terminal that has lost frame synchronization may wish to obtain synchronization and navigation solutions again. In this case, the receiver may already have satellite almanac information or may have received it through another path such as a cellular network, and the receiver may require ephemeris information and/or clock correction parameters of the satellite. A receiver may want to receive subframe 1 and/or subframe 2 to obtain necessary information. At this time, even if the subframe first received by the receiver is subframe 3 or subframe 4, which is a subframe that the receiver does not need, the receiver receives and/or decodes subframe 3 or subframe 4 and then subframes After checking the frame ID, it can be known that the corresponding subframe is a subframe carrying unnecessary information.

As another example, the receiver may only need information delivered in subframes 1 and/or 2 that includes only information different from previously transmitted information (eg, ephemeris information and/or clock correction parameters). That is, when the information included in subframes 1 and/or 2 is the same as the information included in the previous frame, some receivers may not require the corresponding subframe. The ephemeris information and/or clock correction parameters transmitted in subframes 1 and/or 2 may be information that does not change for a certain period of time, and some receivers that have already received the corresponding information may not update the ephemeris information and/or clock correction parameters. There may be no need to receive corresponding ephemeris information and/or clock correction parameters for a period of time. Even in the above case, the receiver can know the need for corresponding information after receiving and/or decoding subframes 1 and/or 2.

As another example, the receiver may require only information delivered in subframe 3 and/or subframe 4. At this time, even if the subframe received by the receiver is subframe 1 or subframe 2, which is a subframe that the receiver does not need, the receiver receives and/or decodes subframe 1 or subframe 2, and the subframe ID After checking, it can be seen that the corresponding subframe is a subframe carrying unnecessary information.

In addition, in the satellite navigation system that transmits and receives the above-described subframes, it is difficult to explicitly transmit frame configuration information when adaptively configuring a frame according to a channel state between a satellite and a region to be serviced.

For example, the satellite navigation system can reduce a frame error rate and a navigation solution derivation time by changing an FEC code rate according to a channel state between a satellite and a service area. For example, a Block IIR-M satellite of GPS may transmit an L2 (1227.60 MHz) CM (civil moderate) channel transmitted at 50 bps at 25 bps using 1/2 code rate FEC by command of the ground station. there is. On the other hand, in the conventional satellite navigation system that transmits and receives the above-described subframes, the receiver may implicitly find the code rate of the FEC, and thus the complexity of the receiver may increase and it is difficult to change the code rate frequently. can

In order to solve the above-mentioned disadvantages, hereinafter, a method and/or apparatus for defining and/or configuring 'subframe characteristics', which is information that summarizes information to be transmitted in a satellite navigation system and/or format characteristics will be explained. In addition, in order to solve the above-mentioned disadvantages, hereinafter, a method of receiving 'subframe characteristic information', which is information summarizing the data characteristics and/or format of a subframe in a satellite navigation system and performing an operation suitable for the characteristics, and/or The device will be described. In addition, in order to solve the above-mentioned disadvantages, hereinafter, a method and/or apparatus for transmitting and receiving 'subframe characteristic information', which is information summarizing information to be transmitted by a subframe and/or format characteristics in a satellite navigation system, and/or an apparatus will be described. It will be.

To this end, in the following, the transmitter may define 'subframe characteristics (eg, subframe elements)', and the transmitter may configure a 'subframe characteristic set' using the subframe characteristic information, , the transmitter may transmit information indicating subframe characteristics within the 'subframe characteristic set' to the receiver.

In addition, the receiver may receive a subframe from the transmitter, the receiver may determine characteristics of the subframe based on information included in the received subframe, and the receiver may perform reception and/or decoding based on the subframe characteristic information. action can be performed. For example, the receiver may identify the format of the subframe by identifying the characteristics of the subframe based on the subframe characteristic information of the received subframe, and the receiver may perform reception and/or decoding suitable for the format of the received subframe. action can be performed. In addition, the receiver can determine the state information of the data of the corresponding subframe, the type and/or change of data contents based on the subframe characteristic information of the received subframe, and the receiver can determine the state information of the data of the subframe, the data contents It is possible to perform a reception and / or decoding operation suitable for the type and / or change of . To this end, the transmitter and the receiver may share subframe characteristics in advance, or the subframe characteristics may be predefined in technical specifications.

Hereinafter, embodiments will be described in detail with reference to the accompanying drawings. However, since various changes can be made to the embodiments, the scope of the patent application is not limited or limited by these embodiments. It should be understood that all changes, equivalents or substitutes to the embodiments are included within the scope of rights. Terms used in the examples are used only for descriptive purposes and should not be construed as limiting. The terminology of the interference signal used in the embodiments is used only for the purpose of explanation and should not be construed as limiting. The singular/plural numbers used in the examples are used only for the purpose of describing the corresponding example, and should not be used for the purpose of limiting the intent.

The satellite navigation system may define 'subframe characteristic information' and configure a 'subframe characteristic set'. The 'subframe characteristic information and/or the information of the 'subframe characteristic set' may be shared by the transmitter and the receiver in advance. 'Subframe characteristic information' may indicate characteristics of data and/or format to be transmitted by the subframe. Subframe characteristic information may be included in a corresponding subframe. Table 5 below may indicate an example of 'subframe characteristic information'.

As an embodiment, when the values of warning flag, idle pattern, satellite signal status, signal health status, URA, message type 0, and UDRA among data of a subframe indicate that data can be used by a general receiver, The corresponding subframe characteristic information' may indicate 'a subframe including information in which data to be transferred is in a good state and has high accuracy'. Or, if at least one of the values of warning flag, idle pattern, satellite signal status, signal health status, URA, message type 0, or UDRA value among subframe data indicates that data is unusable by a general receiver, The corresponding subframe characteristic information' may indicate that 'data is in a bad state or a subframe including information with low accuracy'.

As another embodiment, when a subframe is a subframe using a code rate of 1/2, 'subframe characteristic information' of the corresponding subframe may indicate that it is a 'subframe using a code rate of 1/2'. Alternatively, if channel coding is not used for data to be transmitted by the subframe, 'subframe characteristic information' of the corresponding subframe may indicate that 'data to be transmitted by the corresponding subframe does not use channel coding'. .

As another embodiment, if the satellite navigation system intends to operate like an existing GNSS system without describing subframe characteristics, 'subframe characteristic information' may indicate that 'subframe characteristics are not described'.

As another embodiment, 'subframe characteristic information' may be expressed as a combination of the 'subframe characteristics' as follows. For example, if the state to be transmitted is good in the subframe, the data to be transmitted is information with high accuracy, and the subframe is a subframe using a code rate of 1/2, the characteristics of the above-described subframe are It can be expressed as 'subframe characteristics = data to be transmitted is in a good state and has high accuracy, and a code rate of 1/2 is used for channel coding'. Table 4 below may indicate a first embodiment of a configuration of a 'subframe characteristic set'.

The satellite navigation system may configure a 'subframe characteristic set' that is a set of 'subframe characteristic information'. That is, the satellite navigation system may configure a 'subframe characteristic set' composed of the subframe characteristic information ID. The 'subframe characteristic information and/or information of the 'subframe characteristic set' may be shared by the transmitter and the receiver in advance. can 'Subframe characteristic information' may summarize and express characteristics of data and/or format to be transmitted by the subframe. Table 6 below may indicate a first embodiment of a 'subframe characteristic set' configuration.

Table 7 below may indicate a second embodiment of a configuration of a 'subframe characteristic set'.

Table 8 below may indicate a third embodiment of the configuration of the 'subframe characteristic set'.

Table 9 below may indicate a fourth embodiment of a configuration of a 'subframe characteristic set'.

The configuration of the 'subframe characteristic set' shown in Tables 6 to 9 described above may be shared by the transmitter and the receiver in advance. Using a 'subframe characteristic set' shared by the transmitter and receiver in advance, the transmitter can transmit 'subframe characteristic information' information summarizing the characteristics of the subframe to be transmitted, and the receiver can transmit the characteristics of the subframe to be received. 'Subframe characteristic information' information summarizing may be received. That is, the transmitter may transmit a subframe including the 'subframe characteristic information ID' constituting the 'subframe characteristic set' to the receiver, and the receiver may transmit the 'subframe characteristic information ID' constituting the 'subframe characteristic set'. A subframe including ' may be received from the transmitter.

5 is a flowchart illustrating a first embodiment of a method for transmitting GNSS subframe characteristic information.

Referring to FIG. 5, in the satellite navigation system, a transmitter may define 'subframe characteristic information' (S101), and a transmitter may configure a 'subframe characteristic set' (S102). The transmitter may transmit the previously described configuration of 'subframe characteristic information' and/or 'subframe characteristic set' to the receiver. The transmitter can express the characteristics of the subframe to be transmitted to the receiver as 'subframe characteristic information ID' in the above-described 'subframe characteristic set', and the transmitter transmits the subframe including the 'subframe characteristic information ID' to the receiver. It can (S103).

6 is a flowchart illustrating a first embodiment of a method for receiving GNSS subframe characteristic information.

Referring to FIG. 6, in the satellite navigation system, a receiver may receive an SPS signal (S201), and the receiver may check characteristics of a subframe based on 'subframe characteristic information ID' included in the subframe (S202). ). The receiver may perform a reception and/or decoding operation suitable for the purpose of the receiver or the characteristics of the corresponding subframe based on the checked characteristics of the subframe (S203).

The transmitter and the receiver may share the configuration of sync words and/or the meaning associated with each sync word in advance. Therefore, the receiver can obtain subframe synchronization by receiving and/or identifying the sync word included in the corresponding subframe, and the receiver receives and/or identifies the sync word included in the subframe to obtain the sync word of the received subframe. characteristics can be identified. The receiver may receive and decode data following the sync word according to the identified characteristics of the corresponding subframe, and the receiver may not receive and/or decode data according to the identified characteristics of the corresponding subframe. Depending on the characteristics, it may operate in a sleep mode for a preset time.

As an embodiment, the transmitter may express the 'subframe characteristic information ID' constituting the 'subframe characteristic set' using the sync word of the subframe, and the transmitter transmits the subframe including the above-described sync word to the receiver. can be sent That is, the transmitter can express the characteristics of data to be transmitted in each subframe using different sync words, and can transmit the subframe including the sync word to the receiver.

For example, when a transmitter and a receiver share a subframe characteristic set as shown in Table 6 above in advance, the transmitter may configure different sync words (10001011 01010101 and 11101011 10010000) as shown in Table 10 below, , the transmitter may express 'subframe characteristic information ID' (1 and 2) through sync words (10001011 01010101 and 11101011 10010000). The transmitter and the receiver may share meanings (data characteristics) related to the sync word, the subframe characteristic information ID, and/or the subframe characteristic information ID in advance. When the data state to be transmitted is data unavailable to a general receiver (i.e., at least one of warning flag, idle pattern, satellite health state, signal health state, URA, message type 0, and/or UDRA value) indicates data that a general receiver cannot use), 10001011 01010101 can be configured (or selected) as a sync word. When the data state to be transmitted is available to the receiver (i.e., at least one of the values of warning flag, idle pattern, satellite health status, signal health status, URA, message type 0, and/or UDRA is typical receiver indicates usable data), 11101011 10010000 may be selected as a sync word. The transmitter may transmit a subframe including a sync word expressing 'subframe characteristic information ID' to the receiver.

The sync words (10001011 01010101 and 11101011 10010000) described in the above example are randomly selected values for illustrative purposes, and other arbitrary values may be used. In addition, the length of the sync word described in the above example is an arbitrarily selected value for illustrative purposes, and other arbitrary lengths may be used.

Alternatively, the transmitter may express the subframe ID of each subframe using a different sync word and transmit the subframe including the sync word to the receiver. For example, 10001011 01010101 of different sync words may indicate subframe 1 or 2, and 11101011 10010000 of different sync words may indicate subframe 3 or 4. The receiver can obtain subframe synchronization using the sync word included in the subframe, and the receiver can identify the subframe ID of the corresponding subframe using the sync word expressing the subframe characteristic information ID. Accordingly, the receiver can selectively receive only necessary subframes.

Alternatively, when the transmitter and the receiver share a subframe characteristic set as shown in Table 7 above in advance, the transmitter may configure different sync words (10001011 01010101 and 11101011 10010000) as shown in Table 11 below, and the transmitter may express 'subframe characteristic information ID' (1 and 2) through sync words (10001011 01010101 and 11101011 10010000). The transmitter can select 10001011 01010101 as the sync word when the data of the corresponding subframe uses channel coding of code rate 1/2, and 11101011 10010000 as the sync word when the data of the corresponding subframe does not use channel coding. can choose The transmitter may transmit a subframe including a sync word expressing 'subframe characteristic information ID' to the receiver. The receiver can obtain subframe synchronization using the sync word included in the subframe, and the receiver can determine the code rate used in the corresponding subframe using the sync word included in the subframe. The receiver may perform decoding suitable for the identified 'data characteristic information' (ie, suitable for channel coding used in the corresponding subframe).

Alternatively, when the transmitter and the receiver share the subframe characteristic set as shown in Table 8 above in advance, the transmitter uses different sync words (10001011 01010101, 11101011 10010000, 01010100 01001111, 01101001 11010000, ? ?, and 10101011 10001011). The transmitter may select 10001011 01010101 as the sync word when the state of the data to be transmitted in the corresponding subframe is good and the information is highly accurate, and the corresponding subframe includes information in which the state of the data to be transmitted is poor or accuracy is low. In this case, 11101011 10010000 can be selected as the sync word. The transmitter may select 01010100 01001111 as the sync word when the format of the corresponding subframe uses a format defined by default, and may select 01101001 11010000 as the sync word when the format of the corresponding subframe uses the option 1 format. . The transmitter may transmit a subframe including a sync word expressing 'subframe characteristic information ID' to the receiver. The receiver can obtain subframe synchronization using the sync word included in the subframe, and the receiver can identify characteristics of the corresponding subframe using the sync word included in the subframe. The receiver may perform reception and/or decoding suitable for the identified 'data characteristic information'.

Alternatively, when the transmitter and the receiver share the subframe characteristic set as shown in Table 9 above in advance, the transmitter transmits different sync words (10001011 01010101, 11101011 10010000, 01010100 01001111, 01101001 11010000, ? ?, and 10101011 10001011). The transmitter may select 10001011 01010101 as the sync word when the state of the data to be transmitted in the corresponding subframe is good and the information is highly accurate, and the corresponding subframe includes information in which the state of the data to be transmitted is poor or accuracy is low. In this case, 11101011 10010000 can be selected as the sync word. The transmitter can select 01010100 01001111 as the sync word when the data of the corresponding subframe uses channel coding of code rate 1/2, and 01101001 11010000 as the sync word when the data of the corresponding subframe does not use channel coding. can choose The transmitter may select 10101011 10001011 as a sync word when the subframe ID of the corresponding subframe is 4. The transmitter may transmit a subframe including a sync word expressing 'subframe characteristic information ID' to the receiver. The receiver can obtain subframe synchronization using the sync word included in the subframe, and the receiver can identify characteristics of the corresponding subframe using the sync word included in the subframe. The receiver may perform reception and/or decoding suitable for the identified 'data characteristic information'. For example, when the receiver does not need information transmitted in subframe 4, the receiver does not need to receive data when the sync word included in the received subframe is 10101011 10001011, and enters the sleep mode for a preset time. It can work.

As another embodiment, the transmitter may express the 'subframe characteristic information ID' constituting the 'subframe characteristic set' using a new data format and/or area 'subframe characteristic indicator', and the transmitter may A subframe including a frame characteristic indicator may be transmitted to a receiver. That is, the transmitter can express the characteristics of data to be transmitted in each subframe using the 'subframe characteristic indicator', and can transmit the subframe including the above-described 'subframe characteristic indicator' to the receiver.

7 is a conceptual diagram illustrating a first embodiment of a structure of a subframe including a 'subframe characteristic indicator'.

Referring to FIG. 7, a subframe including a 'subframe characteristic indicator' may have the following structure. A subframe including the 'subframe characteristic indicator' may include a sync word, subframe characteristic information, and/or subframe data. A sync word included in a subframe may consist of the first 16 bits of the subframe. The 'subframe characteristic indicator' included in the subframe may consist of a bits, and the aforementioned a may be a natural number greater than or equal to 1 and less than 584. In addition, the subframe data included in the subframe may be composed of (584 - a) bits. Here, channel coding different from subframe data may be used for the 'subframe characteristic indicator'. Alternatively, channel coding may not be used in the 'subframe characteristic indicator' like the sync word.

For example, when a transmitter and a receiver share a subframe characteristic set as shown in Table 6 above in advance, the 'subframe characteristic indicator' includes bits (eg, as shown in Table 14 below). For example, when a = 8, it can be expressed as 8 bits).

At this time, if the result of combining 8 consecutive bits of the 'subframe characteristic indicator' is positive (+), the receiver may interpret the subframe characteristic information ID = 1, and the receiver may interpret the 'subframe characteristic If the value obtained by combining the consecutive 8 bits of 'indicator' is negative (-), it can be interpreted as subframe characteristic information ID = 0. Alternatively, when the receiver fails to decode the 'subframe characteristic indicator', the receiver may ignore the 'subframe characteristic indicator' and receive subframe data.

8 is a conceptual diagram illustrating a second embodiment of a structure of a subframe including a 'subframe characteristic indicator'.

Referring to FIG. 8, a subframe including a 'subframe characteristic indicator' may have the following structure. A subframe including the 'subframe characteristic indicator' may include a sync word, a subframe characteristic indicator, subframe characteristic information, and/or subframe data. Here, in order to improve the reception performance of the 'subframe characteristic indicator', a diversity technique may be used for the 'subframe characteristic indicator' as follows. For example, the 'first subframe characteristic indicator' may be composed of the first a/2 bits of the subframe (eg, 4 bits when a = 8), and the sync word is 'subframe characteristic'. indicator' and subsequent 16 bits, the 'second subframe characteristic indicator' may consist of a/2 bits subsequent to the sync word, and the subframe data follows the 'second subframe characteristic indicator'. It may consist of (584 - a) bits of

As a third embodiment of the structure of a subframe including a 'subframe characteristic indicator', a part of the 'subframe characteristic indicator' may be positioned at the end of a previous subframe.

)에서 '서브프레임 특성 집합'을 구성하는 '서브프레임 특성 정보 ID'를 싱크 워드를 이용하여 표현할 수 있고, 동시에 송신기는 특정 시간(

)에서 '서브프레임 특성 정보 ID'를 '서브프레임 특성 지시자'를 이용하여 표현할 수도 있다. 즉, 송신기는 특정 시간(

)에서 서브프레임이 전달하고자 하는 데이터의 특성을 표현하는 방법으로서 싱크 워드 또는'서브프레임 특성 지시자'로 혼합하여 표현할 수 있다. 예를 들어, 송신기는 싱크 워드를 계층적으로 구성하여 16 비트의 싱크 워드 중 처음 8 비트들은 서브프레임 특성 집합을 나타내는데 사용하고, 하위 8 비트들은 서브프레임 특성 집합 내의 서브프레임 특성 정보 ID를 나타내는데 사용할 수 있다. As another embodiment, the transmitter is a specific time (

), the 'subframe characteristic information ID' constituting the 'subframe characteristic set' can be expressed using a sync word, and at the same time, the transmitter

), 'subframe characteristic information ID' may be expressed using a 'subframe characteristic indicator'. That is, the transmitter sends a specific time (

), as a method of expressing the characteristics of data to be transmitted by a subframe, it can be expressed by mixing with a sync word or a 'subframe characteristic indicator'. For example, the transmitter hierarchically organizes the Sync Word, and the first 8 bits of the 16-bit Sync Word are used to indicate the subframe characteristic set, and the lower 8 bits are used to indicate the subframe characteristic information ID in the subframe characteristic set. can

) 에서 '서브프레임 특성 집합'을 구성하는 '서브프레임 특성 정보 ID'를 싱크 워드를 이용하여 표현할 수 있고, 다른 시간에 송신기는 특정 시간(예를 들어,

)에서 '서브프레임 특성 정보 ID'를 '서브프레임 특성 지시자'를 이용하여 표현할 수도 있다.As another embodiment, the transmitter is a specific time (

), the 'subframe characteristic information ID' constituting the 'subframe characteristic set' can be expressed using a sync word, and at other times, the transmitter

), 'subframe characteristic information ID' may be expressed using a 'subframe characteristic indicator'.

As another embodiment, the satellite navigation system may switch the 'subframe characteristic set', and in this case, the satellite navigation system takes the 'subframe characteristic set' switching time to prevent frequent 'subframe characteristic set' switching. may be subject to restrictions. That is, the satellite navigation system may be set to perform switching of the 'subframe characteristic set' after a predetermined time.

As another embodiment, by combining the configuration of different sync words and the hierarchical sync word, the first 8 bits of a 16-bit sync word are used to indicate a subframe characteristic set using different sync words, and the lower 8 bits are Different Sync Words may be used to indicate the subframe property information ID in the subframe property set.

In addition, although only some operations of the receiver have been described above, the present application may include other examples of acquiring subframe synchronization using possible combinations and/or methods and extracting characteristic information of a corresponding subframe.

A 'subframe characteristic element' defining a 'subframe characteristic element' that expresses the characteristics of the data that the transmitter intends to transmit in the subframe (eg, status and accuracy, content and type, subframe format including code rate, etc.) Method and / or device for constructing 'subframe characteristic composition tables' consisting of 'subframe characteristic composition table' and 'subframe characteristic element' in 'subframe characteristic composition table' and / or device, transmitter A method and / or device for configuring a subframe including expression information after selecting a 'subframe characteristic element' corresponding to a subframe characteristic, a method and / or device for transmitting a configured subframe by a transmitter, and a method and / or device for transmitting a configured subframe by a receiver A method and/or apparatus for receiving a subframe and identifying subframe characteristics from 'subframe characteristic element' expression information within the subframe, after the receiver identifies the above-described subframe characteristics, suitable for the subframe characteristics and receiver requirements It may include a method and/or device for performing the operation.

Operations suitable for the above-described receiver requirements may include the following.

A method and/or device for determining and determining whether to receive and decode subsequent subframe data after the receiver identifies the above-described subframe characteristics, and after the receiver identifies the subframe characteristics, subsequent corresponding subframe data A method and/or device for determining and determining a reception and decoding method, a method and/or device for saving energy by entering a sleep mode for a certain period when the receiver determines not to receive and decode corresponding subframe data thereafter, and/or device may be included.

Additionally, this application may include: A method and/or device for configuring and transmitting a subframe by selecting a sync word matching the characteristics of data to be transmitted by a transmitter, and a method and/or device for a receiver to receive and identify a sync word and synchronize subframes, and a receiver A method and/or apparatus for determining the characteristics of data to be transmitted in a subframe based on the identified sync word, and after the receiver identifies the characteristics of data to be transmitted in the identified subframe, the subframe after the sync word A method and/or apparatus for determining whether to receive and decode data, or a method for receiving and decoding subframe data following a sync word after the receiver identifies the characteristics of data to be transmitted in the identified subframe, and A method and/or device for determining, and a method and/or device for saving energy by entering a sleep mode for a certain period of time when the receiver determines not to receive and decode subframe data following the sync word.

According to the present application, a transmitter may transmit information summarizing subframe characteristics. Also, according to the present application, the transmitter may adaptively change the format of a subframe and notify the receiver of this. In addition, according to the present application, a receiver can determine subframe characteristics without receiving and decoding subframe data. In addition, according to the present application, the receiver can receive the adaptively transmitted subframe by recognizing the format of the subframe. In addition, according to the present application, the receiver can save energy of the receiver by avoiding unnecessary reception operations, and quickly derive a navigation solution with a low error rate.

In addition, according to the present application, the receiver can identify the characteristics of the subframe to determine state information, data content type and/or change of the data of the corresponding subframe, and perform a reception operation to suit the purpose of the receiver. In addition, according to the present application, the receiver can determine the format of the subframe by identifying the characteristics of the subframe and perform a reception operation suitable for the format.

The operation of the method according to the embodiment of the present invention can be implemented as a computer readable program or code on a computer readable recording medium. A computer-readable recording medium includes all types of recording devices in which information that can be read by a computer system is stored. In addition, computer-readable recording media may be distributed to computer systems connected through a network to store and execute computer-readable programs or codes in a distributed manner.

In addition, the computer-readable recording medium may include hardware devices specially configured to store and execute program instructions, such as ROM, RAM, and flash memory. The program command may include high-level language codes that can be executed by a computer using an interpreter or the like as well as machine code generated by a compiler.

Although some aspects of the present invention have been described in the context of an apparatus, it may also represent a description according to a corresponding method, where a block or apparatus corresponds to a method step or feature of a method step. Similarly, aspects described in the context of a method may also be represented by a corresponding block or item or a corresponding feature of a device. Some or all of the method steps may be performed by (or using) a hardware device such as, for example, a microprocessor, programmable computer, or electronic circuitry. In some embodiments, at least one or more of the most important method steps may be performed by such a device.

In embodiments, a programmable logic device (eg, a field programmable gate array) may be used to perform some or all of the functions of the methods described herein. In embodiments, a field-programmable gate array may operate in conjunction with a microprocessor to perform one of the methods described herein. Generally, methods are preferably performed by some hardware device.

Although the above has been described with reference to preferred embodiments of the present invention, those skilled in the art can variously modify and change the present invention without departing from the spirit and scope of the present invention described in the claims below. You will understand that you can.

Claims (18)

As a method of the first device,
Receiving a subframe including first information that is characteristic information of the subframe from a second device;
Checking a format of the subframe based on the first information; and
Determining whether to decode data included in the subframe based on the confirmed format of the subframe, the method of the first device. The method of claim 1,
The first information is indicated by a sync word included in the subframe, the method of the first device. The method of claim 1,
When it is determined to perform decoding of the data, performing a decoding operation of the data based on coding rate information used for channel coding of the data indicated by the first information The method of the first device, further comprising the step. The method of claim 1,
determining whether or not to receive the data included in the subframe based on the first information before the step of determining whether to decode; and
The method of the first device further comprising operating in a sleep mode for a preset time when it is determined not to receive the data included in the subframe. The method of claim 2,
The method of the first device, characterized in that, when a mapping relationship between the number of the subframe and the first information is preset, the number of the subframe is confirmed based on the sync word. The method of claim 2,
When a mapping relationship between the accuracy of the subframe and the first information is preset, the accuracy of the subframe is determined based on the sync word, and the accuracy is determined based on the sync word included in the subframe. Accuracy of navigation information indicated by data. The method of claim 2,
When a mapping relationship between whether channel coding is used in the subframe and the first information is preset, whether or not channel coding is used in the subframe is confirmed based on the sync word. Characterized in that, Method of the first device. The method of claim 1,
When the subframe includes a sync word, a subframe characteristic indicator, and the data, the first information is indicated by the subframe characteristic indicator, the method of the first device. The method of claim 8,
When a mapping relationship between each of the number and accuracy of a subframe and the first information is set in advance, each of the number and accuracy of the subframe is confirmed by the subframe characteristic indicator, and the accuracy is determined by the subframe. Accuracy of navigation information indicated by the included data. The method of claim 8,
When a mapping relationship between the accuracy of the subframe and the first information is set in advance, the accuracy of the subframe is confirmed based on the subframe characteristic indicator. As a method of the second device,
generating data having a first characteristic;
generating first information indicating the first characteristic;
generating a subframe including a field associated with the first information and the data; and
Transmitting the subframe, wherein the first information is used to determine whether to decode the data included in the subframe. The method of claim 11,
The method of the second device, characterized in that the field is a sync word, and a mapping relationship between the first information and the sync word is preset. The method of claim 11,
The first information,
Characterized in that it indicates coding rate information used for channel coding of the data, wherein the code rate information is used to decode the data. The method of claim 12,
When a mapping relationship between each of the number and accuracy of a subframe and the first information is set in advance, each of the number and accuracy of the subframe is confirmed by the sync word, and the accuracy is included in the subframe Accuracy of navigation information indicated by the data. The method of claim 12,
Characterized in that, when a mapping relationship between whether channel coding is used in the subframe and the first information is preset, the sync word indicates whether channel coding is used in the subframe. device method. As a first device,
processor;
a memory that communicates electronically with the processor; and
includes instructions stored in the memory;
When the instructions are executed by the processor, the instructions cause the first device to:
Receiving a subframe including first information that is characteristic information of a subframe from a second device;
Checking the format of the subframe based on the first information; And
A first device that operates to cause determining whether to decode data included in the subframe based on the confirmed format of the subframe. The method of claim 16
The first information is characterized in that indicated by a sync word included in the subframe, the first device. The method of claim 16
When the subframe includes a sync word, a subframe characteristic indicator, and the data, the first information is indicated by the subframe characteristic indicator.

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