WO2020187274A1 - 随机接入方法及相关装置 - Google Patents

随机接入方法及相关装置 Download PDF

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Publication number
WO2020187274A1
WO2020187274A1 PCT/CN2020/080045 CN2020080045W WO2020187274A1 WO 2020187274 A1 WO2020187274 A1 WO 2020187274A1 CN 2020080045 W CN2020080045 W CN 2020080045W WO 2020187274 A1 WO2020187274 A1 WO 2020187274A1
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Prior art keywords
sequence
random access
seq
satellite
access sequence
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PCT/CN2020/080045
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English (en)
French (fr)
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陈军
刘鹏
李旭
王光健
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华为技术有限公司
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Publication of WO2020187274A1 publication Critical patent/WO2020187274A1/zh

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    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04W—WIRELESS COMMUNICATION NETWORKS
    • H04W74/00—Wireless channel access
    • H04W74/002—Transmission of channel access control information
    • H04W74/004—Transmission of channel access control information in the uplink, i.e. towards network
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04B—TRANSMISSION
    • H04B7/00—Radio transmission systems, i.e. using radiation field
    • H04B7/14—Relay systems
    • H04B7/15—Active relay systems
    • H04B7/185—Space-based or airborne stations; Stations for satellite systems
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04W—WIRELESS COMMUNICATION NETWORKS
    • H04W56/00—Synchronisation arrangements
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04W—WIRELESS COMMUNICATION NETWORKS
    • H04W74/00—Wireless channel access
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04W—WIRELESS COMMUNICATION NETWORKS
    • H04W74/00—Wireless channel access
    • H04W74/002—Transmission of channel access control information
    • H04W74/006—Transmission of channel access control information in the downlink, i.e. towards the terminal
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04W—WIRELESS COMMUNICATION NETWORKS
    • H04W74/00—Wireless channel access
    • H04W74/08—Non-scheduled access, e.g. ALOHA
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04W—WIRELESS COMMUNICATION NETWORKS
    • H04W74/00—Wireless channel access
    • H04W74/08—Non-scheduled access, e.g. ALOHA
    • H04W74/0833—Random access procedures, e.g. with 4-step access
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04W—WIRELESS COMMUNICATION NETWORKS
    • H04W74/00—Wireless channel access
    • H04W74/08—Non-scheduled access, e.g. ALOHA
    • H04W74/0866—Non-scheduled access, e.g. ALOHA using a dedicated channel for access
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04B—TRANSMISSION
    • H04B7/00—Radio transmission systems, i.e. using radiation field
    • H04B7/14—Relay systems
    • H04B7/15—Active relay systems
    • H04B7/185—Space-based or airborne stations; Stations for satellite systems
    • H04B7/1851—Systems using a satellite or space-based relay
    • H04B7/18513—Transmission in a satellite or space-based system
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04W—WIRELESS COMMUNICATION NETWORKS
    • H04W56/00—Synchronisation arrangements
    • H04W56/004—Synchronisation arrangements compensating for timing error of reception due to propagation delay
    • H04W56/0045—Synchronisation arrangements compensating for timing error of reception due to propagation delay compensating for timing error by altering transmission time

Definitions

  • This application relates to the field of communication technology, and in particular to random access methods and related devices.
  • satellite communication Compared with the traditional mobile communication system, satellite communication has a wider coverage and the communication cost has nothing to do with the transmission distance. It can overcome the advantages of natural geographical obstacles such as ocean, desert, and mountains. In order to overcome the shortcomings of traditional communication networks, satellite communication can be used as an effective supplement to traditional networks.
  • satellite communication systems can be divided into the following three types: Geostationary Earth Orbit (GEO) satellite communication systems, also called synchronous orbit satellite systems; Medium Earth Orbit (MEO) satellite communication systems and low Orbit (Low Earth Orbit, LEO) satellite communication system.
  • GEO Geostationary Earth Orbit
  • MEO Medium Earth Orbit
  • LEO Low Earth Orbit
  • the relative speed between the satellite and the ground user is large, resulting in a large Doppler frequency shift of the system.
  • the maximum Doppler frequency shift of a satellite with an orbit height of 700km can reach 80KHz; and the distance between the satellite and the user is long, and the signal The path loss is large and the transmission delay is large. Therefore, designing a random access preamble that is more suitable for satellite communication systems is a crucial issue in satellite communication to ensure communication efficiency and communication quality.
  • This application provides a random access method and device, which can be adapted to long-distance transmission and Doppler frequency shifted communication scenarios, and can be integrated with a cellular network to provide users with wider coverage and better user experience.
  • a random access method including: a user equipment sends a random access sequence, the random access sequence includes: a cyclic prefix, a preamble sequence, and a guard interval; the time length of the cyclic prefix is T CP , the preamble sequence The time length of is T SEQ , and the time length of the guard interval is T GT ; The random access sequence is used for the user equipment to access the satellite, and the maximum cell radius supported by the random access sequence is greater than 100Km;
  • a random access method including: receiving a random access sequence, the random access sequence includes: a cyclic prefix, a preamble sequence, and a guard interval; the time length of the cyclic prefix is T CP , the time of the preamble sequence The length is T SEQ , and the length of the guard interval is T GT ; the random access sequence is used for the user equipment to access the satellite, and the maximum cell radius supported by the random access sequence is greater than 100Km; analytic random access sequence.
  • a random access method including: a user equipment generates a random access sequence according to satellite broadcast information, the random access sequence includes: a cyclic prefix, a preamble sequence and a guard interval; the time length of the cyclic prefix is T CP , the time length of the preamble sequence is T SEQ , and the time length of the guard interval is T GT ; wherein the T SEQ is related to the orbit height of the satellite and the radius of the cell covered by the satellite; the user equipment sends the random access sequence.
  • the sub-carrier spacing of the random access sequence is greater than or equal to 1.25 KHz.
  • the sub-carrier spacing of the random access sequence is 5KHz, 7.5KHz, 15KHz or 30KHz.
  • the subcarrier spacing of the random access sequence is 5KHz, 7.5KHz, 15KHz or 30KHz.
  • T SEQ 1.600 ms or 2.400 ms or 4.800 ms
  • T CP 0.684 ms or 1.828 ms or 2.053 ms
  • T GT 0.716 ms or 0.772 ms or 1.772 ms or 1.147 ms or 2.147ms
  • ⁇ T RTD is the round-trip delay difference.
  • T SEQ 1.600 ms
  • the preamble sequence includes: a first sequence and a second sequence
  • the first sequence is a Zadoff-Chu sequence with root sequence number u
  • the time length of the first sequence and the second sequence is 800 us; wherein, the second sequence is a copy of the Zadoff-Chu sequence with the root sequence number u; or, the second sequence is the root
  • the sequence after the cyclic shift of the Zadoff-Chu sequence with the sequence number u; or, the second sequence is a conjugate sequence of the Zadoff-Chu sequence with the root sequence number (Ncs-u).
  • it further includes: receiving satellite equipment broadcast random access sequence format information; the random access sequence format information is used to indicate the T CP , T of the random access sequence SEQ and T GT ;
  • the generating of the random access sequence by the user equipment includes that the user equipment generates the random access sequence based on the random access sequence allocation information.
  • an embodiment of the present application provides a communication device on the user equipment side.
  • the device may be a user equipment or a chip in the user equipment.
  • the device has the function of realizing the user equipment related to the first aspect or the third aspect. This function can be realized by hardware, or by hardware executing corresponding software.
  • the hardware or software includes one or more units corresponding to the above-mentioned functions.
  • the user equipment when the apparatus is a user equipment, the user equipment includes a processor, a transmitter, and a receiver, and the processor is configured to support the user equipment to perform corresponding functions in the foregoing method.
  • the transmitter and receiver are used to support communication between the user equipment and the satellite.
  • the user equipment may further include a memory, where the memory is used for coupling with the processor and stores necessary program instructions and data of the user equipment.
  • the communication device includes a processing module and a communication module, the communication module includes a sending module, and optionally a receiving module.
  • the processing module generates the random access sequence; the communication module is used to send the random access sequence.
  • the communication module is also used for receiving signaling or data sent by the satellite, for example, receiving the initial TA adjustment value and TA tracking value sent by the satellite.
  • the communication device includes: a controller/processor, a memory, a modem processor, a transmitter, a receiver, and an antenna, which are used to support the communication device to perform the first aspect or the third aspect. The corresponding function in the method.
  • the processor mentioned in any of the above can be a general-purpose central processing unit (Central Processing Unit, CPU for short), microprocessor, application-specific integrated circuit (ASIC for short), or one or more An integrated circuit used to control the program execution of the above-mentioned satellite network communication method.
  • CPU Central Processing Unit
  • ASIC application-specific integrated circuit
  • the communication device includes: a processing module, a sending module, and a receiving module.
  • the determining module is used to determine the time-advanced initial adjustment value information and the time-advanced tracking value information; the sending module, the user sends the initial adjustment value information and the time-advanced tracking value information.
  • the receiving module is used for receiving information sent by the user equipment, for example, receiving a random access sequence sent by the user equipment.
  • the communication device includes: a controller/processor, a memory, a modem processor, a transmitter, a receiver, and an antenna, which are used to support the communication device to execute the corresponding method in the second aspect above Features.
  • the processor mentioned in any of the above can be a general-purpose central processing unit (Central Processing Unit, CPU for short), microprocessor, application-specific integrated circuit (ASIC for short), or one or more An integrated circuit used to control the program execution of the above-mentioned satellite network communication method.
  • CPU Central Processing Unit
  • ASIC application-specific integrated circuit
  • a computer program product containing instructions.
  • the computer program product includes instructions for implementing the method in any one of the first to third aspects above, which when run on a computer, causes the computer to execute the above The method in any one of the first to third aspects or any possible implementation manner thereof.
  • the computer program product may be stored in whole or in part on a storage medium encapsulated in the processor, and may also be stored in whole or in part in a storage medium encapsulated outside the processor.
  • a chip including a processor, configured to call and execute instructions stored in the memory from a memory, so that a communication device installed with the chip executes the methods in the foregoing aspects.
  • another chip including: an input interface, an output interface, a processor, and optionally, a memory.
  • the input interface, the output interface, the processor, and the memory are internally connected
  • the path is connected, the processor is used to execute the code in the memory, and when the code is executed, the processor is used to execute the methods in the foregoing aspects.
  • a device is provided to implement the methods of the foregoing aspects.
  • a wireless communication system in an eleventh aspect, includes the satellite and user equipment involved in the foregoing aspect.
  • the embodiments of the present application also provide another chip, which can become a part of user equipment or satellite equipment.
  • the chip includes: an input interface, an output interface, and a circuit. They are connected by internal connection paths, and the circuits are used to implement the methods in the above examples.
  • FIG. 2 is a schematic flowchart of a random access method according to an embodiment of the application
  • FIG. 3 is a structure of a random access sequence according to an embodiment of the application.
  • Figure 4 is a performance analysis of multiple random access sequences according to an embodiment of the application.
  • FIG. 5 is a schematic diagram of the time-frequency domain of the ZC sequence according to an embodiment of the application.
  • FIG. 6 is a schematic diagram of three preamble sequences according to an embodiment of the application.
  • FIG. 7 is a schematic diagram of a satellite communication scenario according to an embodiment of the application.
  • FIG. 8 is a schematic diagram of simulation of satellite path loss, the farthest coverage distance, and preamble duration according to an embodiment of the application;
  • FIG. 9 is a schematic flowchart of a time advance indication method according to an embodiment of the application.
  • FIG. 10 is a communication device according to an embodiment of the application.
  • FIG. 12 is another communication device according to an embodiment of this application.
  • FIG. 1 shows an exemplary satellite communication system 100 according to an embodiment of the present application.
  • the satellite communication system 100 includes at least one satellite 101 and at least one user equipment 102.
  • the satellite 101 can communicate with the user equipment 102.
  • satellite communication systems can be divided into the following three types: Geostationary Earth Orbit (GEO) satellite communication systems, also called synchronous orbit satellite systems; Medium Earth Orbit (MEO) satellite communication systems and low Orbit (Low Earth Orbit, LEO) satellite communication system.
  • GEO satellites are generally called geostationary orbit satellites with an orbit height of 35786km. Its main advantage is that it is relatively stationary on the ground and provides a large coverage area.
  • the user equipment 102 is a communication device with a wireless communication function.
  • the user equipment can communicate with base stations in a cellular network, and can also communicate with satellites in a satellite communication system.
  • the user equipment may use a communication mode supporting the LTE protocol or the 5G NR protocol to communicate with the base station in the cellular network.
  • the user equipment may communicate with the satellite terminal using a satellite communication protocol compatible with the Long Term Evolution (LTE) protocol or the 5G NR (new radio, NR) protocol.
  • LTE Long Term Evolution
  • 5G NR new radio, NR
  • the user equipment 102 may also be referred to as a terminal device, a mobile station (MS), a mobile terminal (MT), and so on.
  • sites include: mobile phones, tablets, laptops, palmtop computers, mobile internet devices (MID), wearable devices, virtual reality (VR) devices, augmented reality (augmented) Reality, AR) equipment, wireless terminals in industrial control, wireless terminals in self-driving, wireless terminals in remote medical surgery, and wireless terminals in smart grids Terminals, wireless terminals in transportation safety, wireless terminals in smart cities, wireless terminals in smart homes, in-vehicle devices, etc.
  • the embodiment of the present application provides a random access sequence, which can be adapted to long-distance transmission and Doppler shifted communication scenarios, and can be integrated with a cellular network to provide users with wider coverage and better user experience.
  • Figure 2 shows a random access method provided by an embodiment of the present application.
  • the bandwidth of the random access sequence may be 1.08 MHz, including 6 resource blocks (resource blocks).
  • the cyclic prefix (CP) is used to reduce the impact of multipath effects on system performance and reduce the interference between different users; the preamble sequence part can be generated from the Zadoff-Chu root sequence; the guard interval (Guarded Time) is used to prevent interference between this frame of data and the next frame of data.
  • Figure 3 shows a schematic structural diagram of a random access sequence.
  • the user equipment may adopt a contention-based random access mode and a non-contention random access mode.
  • step S200 is further included: the satellite broadcasts random access sequence format information to the user equipment.
  • the random access sequence format information can be carried in SIB2.
  • the user equipment receives the random access sequence format information broadcast by the satellite, and the user equipment generates a random access sequence based on the random access sequence format information.
  • the random access sequence format information includes an index of the preamble format, which is used to indicate the format information of the random access sequence that can be used by the user equipment.
  • the format information includes at least one of T CP , T SEQ and T GI . The corresponding relationship between the index of the preamble format and the format information will be described in detail below.
  • the user equipment sends a random access sequence to the satellite.
  • the satellite may be a satellite whose coverage includes the location of the user equipment.
  • the satellite may be a low-orbit satellite, which uses the low-orbit satellite as an access point for information sent by user equipment, and makes full use of the satellite's wide-area coverage capability to provide users with efficient coverage in the air, ocean, and remote areas.
  • the satellite receives the random access sequence.
  • the user equipment may use a protocol stack compatible with the existing 3GPP LTE or 5G NR to send the random access sequence to the satellite.
  • the satellite also uses a protocol stack compatible with the existing 3GPP LTE or 5G NR to receive the random access sequence sent by the user equipment. Further, the satellite parses the random access sequence.
  • the design of random access sequence needs to consider the time length of the cyclic prefix T CP , the time length of the preamble sequence T SEQ and the time length of the guard interval T GT.
  • the units of T CP , T SEQ and T GT are milliseconds (ms).
  • the duration of T SEQ may be a multiple of 0.8 ms, for example, 1.600, 2.400 ms, or 4.800 ms, etc.
  • the random access sequence of each parameter satisfies: T SEQ ⁇ 0.8ms; T SEQ ⁇ T CP ⁇ T RTD, T SEQ ⁇ T GT ⁇ T RTD, where, ⁇ T RTD for the round trip delay difference.
  • the design of CP duration mainly considers the elimination of the RTD delay difference ⁇ T RTD between users in the coverage cell, and satisfies T CP ⁇ T RTD eliminates the round-trip delay RTD delay difference ⁇ T RTD between users in the coverage cell; GT duration The design mainly considers eliminating the RTD delay difference and the influence of the data of this frame on the data of the next frame, so the design of T GT ⁇ T RTD reduces the influence of the data of this frame on the data of the next frame.
  • the length of T CP is approximately equal to T GT , "substantially equal to” means that T CP is approximately equal to T GT within a certain range, not exactly equal in the absolute sense, but can be substantially equal, for example, T CP ⁇ T GT .
  • the values of T CP , T SEQ and T GT can be combined with each other. In some possible combinations, the values of T CP , T SEQ , and T GT are any of the following groups:
  • T CP 1.828ms
  • T SEQ 2.400ms
  • T GT 0.772ms
  • T CP 1.828ms
  • T SEQ 2.400ms
  • T GT 1.772ms
  • T CP 2.053ms
  • T SEQ 4.800ms
  • T GT 2.147ms.
  • the space of subcarrier (SPS) of the random access sequence is 5KHz, 7.5KHz, 15KHz or 30KHz.
  • SPS subcarrier
  • any group of T CP , T SEQ , and T GT parameters of the random access sequence can be combined with different subcarrier intervals.
  • a preamble format table may include various parameters of the random access sequence, as shown in Table 1 below, the first column in the preamble format table indicates the preamble format index, which may be used to indicate the format information of the random access sequence , The format information of random access includes the parameters on the column corresponding to the index.
  • its preamble sequence format is compatible with NR and LTE, and the number starts from the preamble format index 4, which can be integrated with the cellular network, enabling the same user equipment to support both the cellular network and the satellite
  • the network can provide users with wider coverage and better user experience.
  • the random access sequence format in the embodiment of this application can support a maximum cell radius of 102Km to 308Km, which can adapt to the characteristics of ultra-long-distance coverage of satellite networks, and can provide user equipment with longer-distance coverage and improve
  • the quality of service of the user equipment in the form of Table 1 to Table 3 above, is compatible with 5G or LTE cellular networks.
  • the space of subcarrier (SPS) of the random access sequence is 5KHz, 7.5KHz, 15KHz or 30KHz.
  • SPS subcarrier
  • any group of T CP , T SEQ , and T GT parameters of the random access sequence can be combined with different subcarrier intervals.
  • T CP , T SEQ , T GT and subcarrier spacing can be respectively:
  • T CP 0.684ms
  • T SEQ 1.600ms
  • T GT 0.716ms
  • subcarrier interval 5KHz
  • T CP 0.684ms
  • T SEQ 1.600ms
  • T GT 0.716ms
  • subcarrier interval 15KHz
  • T CP 0.684ms
  • T SEQ 1.600ms
  • T GT 0.716ms
  • subcarrier interval 30KHz
  • T CP 1.828ms
  • T SEQ 2.400ms
  • the subcarrier interval is 5KHz
  • T CP 1.828ms
  • T SEQ 2.400ms
  • the subcarrier spacing is 7.5KHz; or,
  • T CP 1.828ms
  • T SEQ 2.400ms
  • the subcarrier interval is 30KHz
  • T CP 2.053ms
  • T SEQ 4.800ms
  • the subcarrier interval is 5KHz; or,
  • T CP 2.053ms
  • T SEQ 4.800ms
  • the subcarrier spacing is 7.5KHz; or,
  • T CP 2.053ms
  • T SEQ 4.800ms
  • the subcarrier interval is 15KHz; or,
  • T CP 2.053 ms
  • T SEQ 4.800 ms
  • the sub-carrier interval is 30 KHz.
  • the subcarrier spacing under different preamble formats can be as shown in Table 4:
  • the preamble sequence includes: a Zadoff-Chu sequence, and the time length of the Zadoff-Chu sequence is 800 us.
  • the Zadoff-Chu sequence is a constant amplitude, zero autocorrelation sequence.
  • the Zadoff-Chu sequence is also called the ZC sequence.
  • the method for generating the ZC sequence is:
  • the u is called the root number
  • N CS is the length of the ZC sequence
  • N CS and u are relatively prime.
  • the ZC sequence has the following characteristics:
  • the subcarrier interval of the random access sequence in the embodiment of the present application is 5KHz as an example.
  • the left side is the ZC sequence (LTE/ The time-frequency domain schematic diagram of) in the NR
  • the right side is the time-frequency domain schematic diagram of the ZC sequence (provided in this embodiment of the application) with a subcarrier spacing of 5KHz and a duration of 800us.
  • the subcarrier spacing in the right figure is 4 times the subcarrier spacing in the left figure
  • the time domain symbol duration in the right figure is 1/4 of the time domain symbol duration in the left figure.
  • the symbol duration of the ZC sequence is 1/6 of the symbol duration of the ZC sequence in LTE/NR; for the subcarrier of the random access sequence When the interval is 15KHz, the symbol duration of the ZC sequence is 1/12 of the symbol duration of the ZC sequence in LTE/NR; for the case where the subcarrier interval of the random access sequence is 30KHz, the symbol duration of the ZC sequence is 1/24 of the symbol duration of the ZC sequence in LTE/NR.
  • the duration T SEQ of the preamble sequence can be 1600 milliseconds (us), 2400 us or 4800 us.
  • the duration T SEQ of the preamble sequence may be 1600 milliseconds (us)
  • the preamble sequence may include a ZC sequence and a sequence transformed from the ZC sequence, where the ZC sequence and the transformed sequence are in the time domain
  • the length of time is 800us.
  • the ZC sequence with the root sequence number u is the first sequence
  • the sequence obtained by ZC sequence transformation is the second sequence.
  • the methods for obtaining the second sequence from the ZC sequence transformation include but are not limited to the following three:
  • the first method the second sequence is a repetition (copy) of the ZC sequence with the root sequence number u.
  • the first sequence is a ZC sequence with the root sequence number u
  • the second sequence is a repetition of the ZC sequence
  • the second sequence immediately follows the first sequence
  • the duration of the first sequence and the second sequence in the time domain are both 800 us .
  • the first sequence may be generated by formula (1), or may be a cyclic shift sequence of the sequence generated by formula (1).
  • ZC Seq (root num.u) represents a ZC sequence whose root number is u.
  • Rep.ZC (root num.u) means repeating the ZC sequence with root number u, that is, repeating the same root sequence, that is, the same u value.
  • the second sequence is a sequence after the ZC sequence with the root sequence number u is cyclically shifted.
  • the first sequence is the ZC sequence with the root sequence number u
  • the second sequence is the cyclic shift of the ZC sequence with the root sequence number u, wherein the duration of the first sequence and the second sequence in the time domain are both 800 us .
  • Shifted ZC(root num.u) means shifting the ZC sequence of root number u
  • the ZC sequence of root number u is expressed as x u (n)
  • x u ( n) can be generated using the above formula (1)
  • the second sequence can be generated using the following formula (3), where k is the shift number:
  • the second sequence is a conjugate sequence of the ZC sequence whose root sequence number is (N CS -u).
  • the root sequence number of the first 800us ZC sequence (first sequence) is u, which is generated by the above formula (1) and expressed as x u (n);
  • the second sequence is denoted as: Conjugated ZC (root num .u) Sequence.
  • the yoke is conjugate(x v (n)), and the ZC sequence of the last 800us is obtained, which is the second sequence.
  • the duration of the preamble sequence is 2400 us, including the first sequence, the second sequence and the third sequence.
  • the first sequence may be a ZC sequence with root sequence number u, and the second sequence and the third sequence may adopt the first sequence.
  • the third method is generated, so I won’t repeat it here.
  • the preamble sequence may include: a first sequence, a second sequence, a third sequence, and a fourth sequence, where the first sequence may be a ZC sequence with root sequence number u, and the second sequence Sequence, the third sequence and the fourth sequence can be generated using the first to third methods, or the second sequence can be generated from the first sequence using the first to third methods, and then the first sequence and The sequence formed by the second sequence is transformed to obtain the sequence formed by the third sequence and the fourth sequence.
  • the embodiments of the present application provide a random access sequence, so that user equipment can use satellites (for example, low-orbit satellites) as information access points, and make full use of the satellite's wide-area coverage capabilities to form air, ocean, and remote access points. Efficient coverage of the area.
  • the random access sequence can adapt to the characteristics of ultra-long-distance coverage and Doppler frequency shift in the satellite network, and can provide users with wider coverage and better user experience.
  • the embodiment of the application also provides a method for designing random access sequences.
  • the design method takes into account the orbital height of the satellite and the wide-area coverage capability of the satellite, and is designed to be suitable for the ultra-long-distance coverage and the Doppler frequency shift in the satellite network. specialty. It is understandable that the random access sequence involved in the foregoing embodiment can be designed using the method proposed in the embodiment of this application, that is, following the design criterion proposed in the embodiment of the present application.
  • the design of the random access sequence is related to the orbit height of the satellite and the radius of the coverage cell of the satellite.
  • the length of the preamble sequence that is, the minimum value of TSEQ, must meet the transmission delay of cell edge users, that is, the delay extension between different users with a small maximum cell radius supported by the protocol;
  • the sub-carrier spacing ⁇ f of the physical uplink shared channel (PUSCH) data symbol is an integer multiple of the physical random access channel (PRACH) sub-carrier spacing ⁇ f RA .
  • T SEQ must meet the following design criteria:
  • ⁇ f is the subcarrier spacing of the system
  • K is a positive integer
  • N 0 is the thermal noise power density
  • N f is the noise figure of the receiver
  • P RA is the received power.
  • N 0 -174dBm/Hz
  • N f 3.5dB
  • the value is about 16 to 20dB.
  • the receiver refers to a satellite receiver.
  • P RA is the received power of the satellite.
  • P tx is the transmission power
  • G tx is the antenna gain of the transmitter
  • G rx is the antenna gain of the receiver
  • FSL (dB) is the free space path loss.
  • the path loss of FSL free space can be calculated using multiple communication models.
  • f is the carrier frequency; in order to make the designed random access sequence meet the random access of the user equipment at the satellite coverage boundary, let r be the distance between the user equipment at the maximum cell radius boundary from the satellite to the satellite.
  • the FSL may also adopt other communication models suitable for the application scenarios of the embodiments of the present application, for example, a satellite communication model.
  • the distance between the satellite and the user equipment at the boundary of the maximum cell radius of the satellite is related to the orbit height of the satellite and the satellite coverage radius (or the geocentric angle corresponding to the maximum cell radius).
  • the coverage radius can also be called the maximum cell radius of the satellite Or the maximum radius of the coverage cell can be calculated from the satellite's orbit height and the satellite coverage radius (or the geocentric angle corresponding to the maximum cell radius).
  • One method is to determine r based on the satellite's orbital height and geocentric angle. According to Figure 7, the following formula can be used to calculate the distance between the satellite and the user, namely:
  • h is the height of the satellite from the ground, that is, the orbit height of the satellite
  • r E is the radius of the earth.
  • the geocentric angle between the satellite and the ground terminal is ⁇ .
  • the meaning of other parameters are elevation angle Half viewing angle ⁇ , orbit height h.
  • T SEQ ⁇ T CP ⁇ T RTD
  • T SEQ ⁇ T GT ⁇ T RTD
  • ⁇ T RTD for the round trip delay difference
  • the design of CP mainly needs to consider eliminating the round trip delay (RTD) delay difference between users in the coverage cell, so the CP length needs to meet the design criterion 1: T SEQ ⁇ T CP ⁇ ⁇ T RTD ; GT design
  • the main consideration is to eliminate the RTD delay difference and the impact of the data of this frame on the data of the next frame, so the GT length needs to meet the design criterion 2: T SEQ ⁇ T GT ⁇ ⁇ T RTD .
  • the length of T CP may be approximately equal to T GT .
  • T SEQ , T CP , and T GT can be obtained.
  • the duration of T SEQ is a multiple of 0.800 ms, for example, 1.600 ms, 2.400 ms, or 4.800 ms, etc.
  • the space of subcarrier (SPS) of the random access sequence is 5KHz, 7.5KHz, 15KHz or 30KHz.
  • SPS subcarrier
  • the random access sequence satisfies any of the following groups:
  • T CP 0.684ms
  • T SEQ 1.600ms
  • T GT 0.716ms
  • subcarrier interval 5KHz
  • T CP 0.684ms
  • T SEQ 1.600ms
  • T GT 0.716ms
  • sub-carrier spacing is 7.5KHz
  • T CP 0.684ms
  • T SEQ 1.600ms
  • T GT 0.716ms
  • subcarrier interval 15KHz
  • T CP 1.828ms
  • T SEQ 2.400ms
  • the subcarrier interval is 15KHz
  • T CP 2.053ms
  • T SEQ 4.800ms
  • the subcarrier spacing is 7.5KHz; or,
  • T CP 2.053 ms
  • T SEQ 4.800 ms
  • the sub-carrier interval is 30 KHz.
  • the embodiments of the present application provide a random access sequence, so that user equipment can use satellites (for example, low-orbit satellites) as information access points, and make full use of the satellite's wide-area coverage capabilities to form air, ocean, and remote access points. Efficient coverage of the area.
  • the random access sequence can adapt to the characteristics of ultra-long-distance coverage and Doppler frequency shift in the satellite network, and can provide users with wider coverage and better user experience.
  • the user equipment and/or the satellite equipment can generate random access sequences in multiple ways.
  • the duration of T SEQ is a multiple of 0.800ms, for example, 1.600ms, 2.400ms, or 4.800ms, etc. .
  • the space of subcarrier (SPS) of the random access sequence is 5KHz, 7.5KHz, 15KHz or 30KHz.
  • the user equipment and the satellite can exchange the format information of the random access sequence in the following ways, including but not limited to the following ways:
  • both the user equipment and the satellite equipment store a random access sequence format table
  • the random access sequence format table includes: format information of the random access sequence corresponding to the format index, and the format information includes the cyclic prefix
  • the time length T CP , the time length T SEQ of the preamble sequence and the time length T GT of the guard interval optionally, also include the sub-carrier interval corresponding to the format index.
  • the values of T CP , T SEQ and T GT and the values of subcarrier spacing can be combined with each other to form multiple combinations.
  • the random access format table includes one or more of multiple combinations of T CP , T SEQ and T GT and subcarrier spacing. For example, Table 1 to Table 4 above.
  • the random access sequence format table can be stored in a protocol agreed upon by the user equipment and the satellite device; in the second method, the random access sequence format table can be used by the satellite
  • the system parameter is sent to the user equipment, and the user equipment stores the random access sequence format table after receiving it.
  • the random access format information broadcast by the satellite device may include a format index. Therefore, the user equipment that receives the format index can look up the table to determine the format information of the random access sequence corresponding to the format index. Based on the first implementation manner, the signaling overhead can be effectively saved and the transmission efficiency can be improved.
  • the random access sequence format information sent by the satellite device includes the format information of a random access sequence to be allocated to the user equipment, and the identity of the user equipment, the The identification of the user equipment may report the MAC address or IP address of the user equipment, or the satellite network address assigned to the user equipment by the satellite.
  • This method can be applied to the situation where only the satellite device stores the above-mentioned random access sequence format table, and it can also be applied to the situation where both the user equipment and the satellite equipment store the above-mentioned random access sequence format table. Based on the second implementation manner, the storage space of the user equipment is saved, and the robustness of transmission is improved.
  • the user equipment does not store the random access sequence format table, and the satellite equipment may or may not store the random access sequence format table.
  • the random access sequence format information includes the ephemeris information of the satellite; in one example, the ephemeris information may include the position information of the satellite (orbital height, latitude and longitude, etc.) and the operating period of the satellite.
  • the user equipment can obtain its own GPS location information based on GPS satellites or ground base stations.
  • the user equipment uses the position information of the satellite and its own position information to calculate the parameters in the random access sequence based on the design criteria involved in the foregoing embodiment, for example, Formula 4 to Formula 7, or equivalent variants thereof.
  • Formula 4 to Formula 8 may be stored in the user equipment.
  • the storage space of the user equipment can be saved, and the user equipment can flexibly adjust the format of the random access sequence in real time according to the orbit height of the satellite, which improves flexibility.
  • neither the user equipment nor the satellite equipment stores the random access sequence format table.
  • the satellite equipment can use formula 4 to formula 8 or the like based on the satellite's orbit height and the cell radius corresponding to the satellite's coverage area. Effective deformation or substitution form, and design criteria, calculate the parameters in the random access sequence, and deliver the calculated parameters to the user equipment.
  • the storage space of the user equipment and the satellite can be saved, and the satellite can flexibly adjust the format of the random access sequence in real time according to the orbit height of the satellite, and the calculation speed is fast and the flexibility is improved.
  • the embodiment of the application provides a random access sequence, which is more robust so that user equipment can use satellites (for example, low-orbit satellites) as information access points, and make full use of the satellite wide-area coverage capabilities to form a pair of Efficient coverage of air, sea, and remote areas.
  • the random access sequence can adapt to the characteristics of ultra-long-distance coverage and Doppler frequency shift in the satellite network, and can provide users with wider coverage and better user experience.
  • the embodiment of the present application also provides a time advance (TA) indication method. As shown in Figure 9, including:
  • S901 The satellite sends initial adjustment value information of a time advance (TA); where the initial adjustment value information is used to indicate the initial adjustment value of the time advance to the user equipment.
  • TA time advance
  • the user equipment can implement the preliminary adjustment of the timing advance based on the initial adjustment value.
  • the user equipment can realize the fine adjustment of the time advance based on the tracking value information.
  • the initial adjustment value information and tracking value information can be carried in a variety of different ways:
  • the initial adjustment value information is carried in the random access channel response (RACH Response, RAR) time advance TA control (Time Advance Command) field.
  • RACH Response RAR
  • time advance TA control Time Advance Command
  • the random access channel response complies with the LTE standard
  • the initial adjustment value information is carried in the TA control field of LTE RAR
  • the random access channel response complies with the 5G NR standard
  • the initial adjustment value information is carried in NR RAR
  • the TA control field By adopting the foregoing two methods, compatibility with the cellular network can be achieved, and the complexity of user equipment design can be reduced.
  • the tracking value information is carried in the time advance (TA) field of the media access control element.
  • the minimum time unit of the tracking value is TS2 (sampling time, TS).
  • the step length of the tracking value adjustment is 16 times TS2, TA tracking
  • the adjustment range of the value is (-16.7us, 16.7us).
  • the tracking value information may include multiple bits to indicate the tracking value, and the number of bits of the multiple bits is greater than 6.
  • the tracking value information includes 8 bits.
  • the user equipment that receives the TA adjustment information may perform coarse-grained initial adjustment of the time advance based on the initial value, and further perform fine-grained tracking adjustment based on the tracking value.
  • the user equipment may use the following TA adjustment formula for adjustment:
  • N TA,new N TA,old +(T A -127) ⁇ 16
  • the embodiment of this application designs a timing advance adjustment method suitable for satellite communication systems, and the timing advance indication is compatible with the timing advance indication of LTE or 5G NR, which can not only provide user equipment with a larger range of coverage, but also It can simplify the design of satellite communication system and realize the integration of cellular network and satellite network.
  • the communication device 1000 includes: a processing module 1001 and a communication module 1002.
  • the processing module 1001 may be used to generate a random access sequence, the random access sequence includes: a cyclic prefix, a preamble sequence, and a guard interval; the time length of the cyclic prefix is T CP , and the time length of the preamble sequence Is T SEQ , and the time length of the guard interval is T GT .
  • the processing module 1001 may also be used to parse the TA initial adjustment value information and TA tracking value information. For example, it is used to implement step S201, or it is used to control the communication module 1002 to implement step S202.
  • the communication module 1002 is used to send a random access sequence.
  • the communication module 1002 may include a cellular communication module and a satellite communication module.
  • the cellular communication module enables the communication device 1000 to communicate with the cellular network using a wireless communication protocol (such as LTE or 5G NR protocol).
  • the satellite communication module A protocol compatible with the LTE or 5G NR protocol can be used to communicate with the satellites in the satellite network.
  • the communication module 1002 also includes a receiving module and a sending module.
  • the communication module 1002 can also be used to send the TA initial modulation value and tracking value. For example, it is used to implement the random access sequence in step S202, or to receive the timing advance adjustment information in step S901 or step S903.
  • the embodiment of the present application also provides a communication device 1100.
  • the communication device 1100 can be applied to the user equipment side, and can be used to implement the methods and steps related to the user equipment in the foregoing embodiments.
  • the user equipment may be a communication device located on the ground segment as shown in FIG. 1, for example, a user terminal, a satellite terminal, a cellular terminal, a ground station, a cellular base station, and an access point.
  • the communication device may be user equipment or a chip in the user equipment.
  • the user equipment is a terminal device.
  • FIG. 11 shows a simplified schematic diagram of a possible design structure of the user equipment involved in the foregoing embodiment.
  • the user equipment includes a transmitter 1101, a receiver 1102, a controller/processor 1103, a memory 1104, and a modem processor 1105.
  • the transmitter 1101 adjusts (for example, analog conversion, filtering, amplification, and upconversion, etc.) the output samples and generates an uplink signal, which is transmitted to the satellite described in the above-mentioned embodiment via an antenna.
  • the antenna receives the downlink signal transmitted by the satellite in the above embodiment.
  • the receiver 1102 adjusts (e.g., filters, amplifies, downconverts, and digitizes, etc.) the signal received from the antenna and provides input samples.
  • the encoder 1106 receives service data and signaling messages to be sent on the link, and processes the service data and signaling messages (for example, formatting, encoding, and interleaving).
  • the modulator 1107 further processes (for example, symbol mapping and modulation) the encoded service data and signaling messages and provides output samples.
  • the demodulator 11011 processes (e.g., demodulates) the input samples and provides symbol estimates.
  • the decoder 1108 processes (e.g., deinterleaves and decodes) the symbol estimates and provides decoded data and signaling messages sent to the user equipment.
  • the encoder 1106, the modulator 1107, the demodulator 11011, and the decoder 1108 can be implemented by a synthesized modem processor 1105.
  • the controller/processor 1103 controls and manages the actions of the user equipment, and is used to execute the processing performed by the user equipment in the foregoing embodiment.
  • the memory 1103 is used to store program codes and data of the user equipment.
  • the embodiment of the present application provides a communication device 1200, which can be applied to a satellite terminal, and can be used to implement the methods and steps related to the satellite in the foregoing embodiments.
  • the communication device may be a satellite 121 as shown in FIG. 1.
  • the communication device can also be a chip in a satellite.
  • the communication device 1200 includes a processing module 1201, a sending module 1202, and optionally, a receiving module 1203.
  • the processing module 1201 can parse the received random access sequence.
  • the processing module 1201 may also be used to generate TA initial value information and TA adjustment value information.
  • the receiving module 1202 is configured to receive the random access sequence sent by the user equipment.
  • the receiving module is used to implement S203.
  • the sending module 1203 is configured to send TA initial value information and TA adjustment value information to the user equipment.
  • the sending module is used to implement S902.
  • T CP the description of T CP , T SEQ and T GT and the sub-carrier spacing can be referred to the description of the previous embodiment, which will not be repeated here.
  • sending in the foregoing embodiment may also refer to “providing” or “output”; the action of “receiving” may also refer to “obtaining” or “input”.
  • the embodiments of the present application also provide a computer storage medium, the computer-readable storage medium stores instructions, and the instructions can be executed by one or more processors on the processing circuit. When it runs on a computer, it makes the computer execute the methods described in the above aspects.
  • the embodiments of the present application also provide a chip system that includes a processor for supporting distributed units, centralized units, and satellites or user equipment to implement the functions involved in the above embodiments, such as generating or processing The data and/or information involved in the above methods.
  • the chip system may further include a memory for storing necessary program instructions and data for distributed units, centralized units, satellites or user equipment.
  • the chip system can be composed of chips, or include chips and other discrete devices.
  • the embodiment of the present application also provides another chip, including: an input interface, an output interface, a processor, and a memory.
  • the input interface, the output interface, the processor, and the memory are connected by an internal connection path.
  • the processor is configured to execute the code in the memory, and when the code is executed, the processor is configured to execute the methods in the foregoing examples.
  • the embodiment of the present application also provides another chip, which can become a part of user equipment or satellite.
  • the chip includes: an input interface, an output interface and a circuit.
  • the input interface, the output interface and the circuit pass through The internal connection paths are connected, and the circuit is used to implement the methods in the above examples.
  • the embodiments of the present application also provide a computer program product containing instructions, which, when running on a computer, enables the computer to execute methods and functions involving satellites or user equipment in any of the foregoing embodiments.
  • An embodiment of the present application also provides a communication system, which includes the satellite and at least one user equipment involved in the foregoing embodiment.
  • the embodiments of the present application also provide a device for implementing the methods in the foregoing embodiments.
  • the computer program product includes one or more computer instructions.
  • the computer may be a general-purpose computer, a special-purpose computer, a computer network, or other programmable devices.
  • the computer instructions may be stored in a computer-readable storage medium or transmitted from one computer-readable storage medium to another computer-readable storage medium. For example, the computer instructions may be transmitted from a website, computer, server, or data center.
  • the computer-readable storage medium may be any available medium that can be accessed by a computer or a data storage device such as a server or a data center integrated with one or more available media.
  • the usable medium may be a magnetic medium (for example, a floppy disk, a hard disk, and a magnetic tape), an optical medium (for example, a DVD), or a semiconductor medium (for example, a solid state disk).

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Abstract

本申请公开了一种随机接入方法，由用户设备向卫星发送随机接入序列，以接入卫星，随机接入序列包括：循环前缀、前导码序列和保护间隔；循环前缀的时间长度为T CP，前导码序列的时间长度为T SEQ，保护间隔的时间长度为T GT，随机接入序列支持的最大小区半径大于100Km；基于此方案，用户设备可接入卫星，能够适应于远距离传输，大多普勒频移的通信场景，为用户提供更广的覆盖。

Description

随机接入方法及相关装置
本申请要求在2019年03月19日提交中国专利局、申请号为201910207566.4、发明名称为“随机接入方法及相关装置”的中国专利申请的优先权，其全部内容通过引用结合在本申请中。
技术领域
本申请涉及通信技术领域，特别涉及随机接入方法及相关装置。
背景技术
未来的第五代移动网络(5th generation mobile networks,5G)及5G演进网络，一方面需要满足各行各业的业务需求，另一方面还需要提供更广的业务覆盖。然而，当前地面移动通信网络有限的覆盖能力，已经不能满足人们在任意时间、任意地点获取信息的需求；而且当前基于基站覆盖的模式来提供超广域的覆盖对于偏远地区、沙漠、海洋和空中等场景存在经济性和可行性方面的巨大挑战。
卫星通信相对于传统的移动通信系统，其拥有更广的覆盖范围以及通信成本与传输距离无关，可以克服海洋，沙漠，高山等自然地理障碍等优点。为了克服传统通信网的不足，卫星通信可以作为传统网络的一个有效的补充。
根据轨道高度的不同可以将卫星通信系统区分为如下三种：高轨(Geostationary Earth Orbit,GEO)卫星通信系统，也称同步轨道卫星系统；中轨(Medium Earth Orbit,MEO)卫星通信系统和低轨(Low Earth Orbit,LEO)卫星通信系统。
卫星通信系统中卫星与地面用户相对速度大，导致系统的多普勒频移较大，如轨道高度为700km的卫星，其最大多普勒频移可达80KHz；且卫星与用户距离远，信号的路径损耗大，传输时延大。因此，设计更适应于卫星通信系统的随机接入前导码是卫星通信中保障通信效率和通信质量至关重要的问题。
发明内容
本申请提供了随机接入方法及其装置，能够适应于远距离传输，大多普勒频移的通信场景，可与蜂窝网络融合，为用户提供更广的覆盖和更好的用户体验。
第一方面，提供一种随机接入方法，包括：用户设备发送随机接入序列，随机接入序列包括：循环前缀、前导码序列和保护间隔；循环前缀的时间长度为T CP，前导码序列的时间长度为T SEQ，保护间隔的时间长度为T GT；所述随机接入序列用于所述用户设备接入所述卫星，所述随机接入序列支持的最大小区半径大于100Km；
第二方面，提供一种随机接入方法，包括：接收随机接入序列，随机接入序列包括：循环前缀、前导码序列和保护间隔；循环前缀的时间长度为T CP，前导码序列的时间长度为T SEQ，保护间隔的时间长度为T GT；所述随机接入序列用于所述用户设备接入所述卫星，所述随机接入序列支持的最大小区半径大于100Km；解析随机接入序列。
第三方面，提供一种随机接入方法，包括：用户设备根据卫星的广播信息生成随机接入序列，随机接入序列包括：循环前缀，前导码序列和保护间隔；循环前缀的时间长度为T CP，前导序列的时间长度为T SEQ，保护间隔的时间长度为T GT；其中所述T SEQ与的卫 星的轨道高度和卫星的覆盖小区半径有关；用户设备发送所述随机接入序列。
在上述任一方面的一种可能的设计中，随机接入序列的子载波间隔大于等于1.25KHz。例如，随机接入序列的子载波间隔为5KHz,7.5KHz,15KHz或30KHz。
在上述任一方面的一种可能的设计中，随机接入序列的子载波间隔为5KHz,7.5KHz,15KHz或30KHz。
在上述任一方面的一种可能的设计中，T SEQ≥T CP≥ΔT RTD，T SEQ≥T GT≥ΔT RTD，其中，ΔT RTD为往返时延差。
在上述任一方面的一种可能的设计中，T SEQ＝1.600ms或2.400ms或4.800ms；T CP＝0.684ms或1.828ms或2.053ms；T GT＝0.716ms或0.772ms或1.772ms或1.147ms或2.147ms；其中，ΔT RTD为往返时延差。
在上述任一方面的一种可能的设计中，T CP＝0.684ms,T SEQ＝1.600ms，T GT＝0.716ms，所述子载波间隔为5KHz；或，T CP＝0.684ms,T SEQ＝1.600ms，T GT＝0.716ms，所述子载波间隔为7.5KHz；或，T CP＝0.684ms,T SEQ＝1.600ms，T GT＝0.716ms，所述子载波间隔为15KHz；或，T CP＝1.828ms,T SEQ＝2.400ms，T GT＝0.772ms或T GT＝1.772ms，所述子载波间隔为7.5KHz；或，T CP＝1.828ms,T SEQ＝2.400ms，T GT＝0.772ms或T GT＝1.772ms，所述子载波间隔为15KHz；或，T CP＝1.828ms,T SEQ＝2.400ms，T GT＝0.772ms或T GT＝1.772ms，所述子载波间隔为30KHz；或，T CP＝2.053ms,T SEQ＝4.800ms，T GT＝1.147ms或T GT＝2.147ms，所述子载波间隔为7.5KHz；或，T CP＝2.053ms,T SEQ＝4.800ms，T GT＝1.147ms或T GT＝2.147ms，所述子载波间隔为15KHz；或，T CP＝2.053ms,T SEQ＝4.800ms，T GT＝1.147ms或T GT＝2.147ms，所述子载波间隔为30KHz。
在上述任一方面的一种可能的设计中，T SEQ＝1.600ms，所述前导码序列包括：第一序列和第二序列，所述第一序列为根序号为u的Zadoff-Chu序列，所述第一序列和所述第二序列的时间长度为800us；其中，所述第二序列为所述根序号为u的Zadoff-Chu序列的复制；或，所述第二序列为所述根序号为u的Zadoff-Chu序列循环移位后的序列；或，所述第二序列为根序号为(Ncs-u)的Zadoff-Chu序列的共轭序列。
在上述第一方面的的一种可能的设计中，还包括：接收卫星设备广播随机接入序列格式信息；所述随机接入序列格式信息用于指示所述随机接入序列的T CP，T SEQ和T GT；
所述用户设备生成随机接入序列，包括，所述用户设备基于所述随机接入序列分配信息生成所述随机接入序列。
在上述第二方面的一种可能的设计中，还包括：卫星广播随机接入序列格式信息，所述随机接入序列格式信息用于指示所述随机接入序列的T CP，T SEQ和T GT。
在上述任一方面的一种可能的设计中，所述格式信息包括格式索引，格式索引取第一值或第二值或第三值，对应T CP＝0.684ms,T SEQ＝1.600ms，T GT＝0.716ms；
所述格式索引取第四值，对应T CP＝1.828ms,T SEQ＝2.400ms，T GT＝0.772ms或，T CP＝1.828ms,T SEQ＝2.400ms，T GT＝1.772ms；
所述格式索引取第五值，对应T CP＝2.053ms,T SEQ＝4.800ms，T GT＝1.147ms；或，T CP＝2.053ms,T SEQ＝4.800ms，T GT＝2.147ms。
第四方面，本申请实施例提供一种用户设备端的通信装置，该装置可以是用户设备，也可以是用户设备内的芯片。该装置具有实现上述第一方面或第三方面涉及用户设备的功能。 该功能可以通过硬件实现，也可以通过硬件执行相应的软件实现。该硬件或软件包括一个或多个与上述功能相对应的单元。
在一种可能的实现方式中，当该装置为用户设备时，用户设备包括：处理器、发送器和接收器，所述处理器被配置为支持用户设备执行上述方法中相应的功能。发送器和接收器用于支持用户设备和卫星之间的通信。可选的，用户设备还可以包括存储器，所述存储器用于与处理器耦合，其保存用户设备必要的程序指令和数据。
在另一种可能的实现方式中，该通信装置包括：处理模块、通信模块，通信模块包括发送模块，可选的还包括接收模块。处理模块生成随机接入序列；通信模块，用于发送随机接入序列。通信模块，还用于接收卫星发送的信令或数据，例如，接收卫星发送的TA初始调整值和TA跟踪值。
在又一个可能的实现方式中，该通信装置包括：控制器/处理器，存储器，调制解调处理器，发射器，接收器，天线，用于支持通信装置执行上述第一方面或第三方面方法中相应的功能。
上述任一处提到的处理器，可以是一个通用中央处理器(Central Processing Unit，简称CPU)，微处理器，特定应用集成电路(application-specific integrated circuit，简称ASIC)，或一个或多个用于控制上述各方面卫星网络的通信方法的程序执行的集成电路。
第五方面，本申请实施例提供一种卫星端的通信装置，该装置可以是卫星，也可以是卫星内的芯片。该装置具有实现上述第二方面涉及卫星的功能。该功能可以通过硬件实现，也可以通过硬件执行相应的软件实现。该硬件或软件包括一个或多个与上述功能相对应的单元。
在一种可能的实现方式中，当该装置为卫星时，用户设备包括：处理器、发送器和接收器，所述处理器被配置为支持卫星执行上述方法中相应的功能。发送器和接收器用于支持用户设备和卫星之间的通信。可选的，卫星还可以包括存储器，所述存储器用于与处理器耦合，其保存卫星必要的程序指令和数据。
在另一种可能的实现方式中，该通信装置包括：处理模块、发送模块和接收模块。确定模块用于确定时间提前的初始调整值信息和时间提前的跟踪值信息；发送模块，用户发送初始调整值信息和时间提前的跟踪值信息。接收模块，用于接收用户设备发送的信息，例如，接收用户设备发送的随机接入序列。
在又一个可能的实现方式中，该通信装置包括：控制器/处理器，存储器，调制解调处理器，发射器，接收器，天线，用于支持通信装置执行上述第二方面方法中相应的功能。
上述任一处提到的处理器，可以是一个通用中央处理器(Central Processing Unit，简称CPU)，微处理器，特定应用集成电路(application-specific integrated circuit，简称ASIC)，或一个或多个用于控制上述各方面卫星网络的通信方法的程序执行的集成电路。
第六方面，本申请提供了一种计算机可读存储介质，所述计算机可读存储介质中存储有指令，所述指令可以由处理电路上的一个或多个处理器执行。当其在计算机上运行时，使得计算机执行上述第一方面或第二方面或第三方面中的方法。
第七方面，提供了一种包含指令的计算机程序产品，该计算机程序产品包括用于实现上述第一方面至第三方面中任一方面方法的指令，其在计算机上运行时，使得计算机执行上述第一方面至第三方面中任一方面或其任意可能的实现方式中的方法。该计算机程序产品可全部或部分的存储于封装于处理器当中的存储介质上，还可以全部或部分的存储在封装于处理器之外的存储介质中。
第八方面，提供了一种芯片，包括处理器，用于从存储器中调用并运行所述存储器中存储的指令，使得安装有所述芯片的通信设备执行上述各方面中的方法。
第九方面，提供另一种芯片，包括：输入接口、输出接口、处理器，可选的，还包括存储器，所述输入接口、输出接口、所述处理器以及所述存储器之间通过内部连接通路相连，所述处理器用于执行所述存储器中的代码，当所述代码被执行时，所述处理器用于执行上述各方面中的方法。
第十方面，提供一种装置，用于实现上述各方面的方法。
第十一方面，提供一种无线通信系统，该系统包括上述方面涉及的卫星和用户设备。
本申请实施例还提供另一种芯片，该芯片可以成为用户设备或卫星设备的一部分，该芯片包括：输入接口、输出接口和电路，所述输入接口、所述输出接口与所述电路之间通过内部连接通路相连，所述电路用于执行上述各示例中的方法。
附图说明
图1为本申请实施例的一种应用场景示例；
图2为本申请实施例的一种随机接入方法流程示意图；
图3为本申请实施例的一种随机接入序列的结构；
图4为本申请实施例的多种随机接入序列的性能分析；
图5为本申请实施例的ZC序列的时频域示意图；
图6为本申请实施例的三种前导码序列的示意图；
图7为本申请实施例的一种卫星通信场景的示意图；
图8为本申请实施例的卫星的路径损耗和最远覆盖距离与前导码时长的仿真示意图；
图9为本申请实施例的一种时间提前指示方法的流程示意图；
图10为本申请实施例的一种通信装置；
图11为本申请实施例的另一种通信装置；
图12为本申请实施例的又一种通信装置；
具体实施方式
本申请的实施方式部分使用的术语仅用于对本申请的具体实施例进行解释，而非旨在限定本申请。
图1示出了本申请实施例的一种示例性的卫星通信系统100，卫星通信系统100中包括至少一个卫星101，和至少一个用户设备102。卫星101可以与用户设备102进行通信。
根据轨道高度的不同可以将卫星通信系统区分为如下三种：高轨(Geostationary Earth Orbit,GEO)卫星通信系统，也称同步轨道卫星系统；中轨(Medium Earth Orbit,MEO)卫星通信系统和低轨(Low Earth Orbit,LEO)卫星通信系统。GEO卫星一般又称为静止轨道卫星，轨道高度35786km，其主要的优点是相对地面静止并且提供很大的覆盖面积。然而由于GEO卫星轨道卫星缺点也相对突出：如距离地球距离过大，需要较大口径的天线；其传输时延较大，在0.5秒左右，无法满足实时业务的需求；同时其轨道资源相对紧张，发射成本高并且无法为两极地区提供覆盖。MEO卫星，轨道高度位于2000-35786km，拥有相对较少的卫星数目即可以实现全球覆盖，但是其传输时延相比LEO卫星较高，其主要的用于定位导航。轨道高度在300-2000km称为低轨卫星(LEO)，LEO卫星比MEO和GEO轨道高度低，数据传播 时延小，功率损耗更小，发射成本相对更低。因此LEO卫星通信网络在近年来取得了长足进展，受到关注。
用户设备102为一种具有无线通信功能的通信装置。该用户设备可以与蜂窝网络中的基站进行通信，还可以与卫星通信系统中的卫星进行通信。一个示例中，该用户设备可以采用支持LTE协议或5G NR协议的通信模式与蜂窝网络中的基站进行通信。一个示例中，该用户设备可以采用与长期演进技术(Long Term Evolution，LTE)协议或5G NR(new radio,NR)协议兼容的卫星通信协议与卫星终端进行通信。
用户设备102又可以称之为终端设备、移动台(mobile station，MS)、移动终端(mobile terminal，MT)等。一些站点的举例包括：手机(mobile phone)、平板电脑、笔记本电脑、掌上电脑、移动互联网设备(mobile internet device，MID)、可穿戴设备，虚拟现实(virtual reality，VR)设备、增强现实(augmented reality，AR)设备、工业控制(industrial control)中的无线终端、无人驾驶(self driving)中的无线终端、远程手术(remote medical surgery)中的无线终端、智能电网(smart grid)中的无线终端、运输安全(transportation safety)中的无线终端、智慧城市(smart city)中的无线终端、智慧家庭(smart home)中的无线终端、车载设备等。
本申请实施例提供一种随机接入序列，能够适应于远距离传输，大多普勒频移的通信场景，可与蜂窝网络融合，为用户提供更广的覆盖和更好的用户体验。
图2示出了本申请实施例提供的一种随机接入方法。
201、用户设备生成随机接入序列，所述随机接入序列包括：循环前缀，前导码序列和保护间隔；该随机接入序列用于用户设备接入所述卫星。
所述循环前缀的时间长度为Tcp，所述前导码序列的时间长度为TSEQ，所述保护间隔的时间长度为TGT；为适应于远距离传输，大多普勒频移的通信场景，所述随机接入序列的设计需满足：可支持的最大小区半径需大于100千米(Kilometer，Km)；以及，随机接入序列的子载波间隔大于等于1.25KHz。在一个可能的设计中，随机接入序列与卫星的轨道高度和卫星的覆盖小区半径相关。
可选的，该随机接入序列的带宽可以为1.08MHz，包括6个资源块(resource block)。其中，循环前缀(cyclic prefix，CP)用于降低多径效应对系统性能的影响以及减少不同用户间的干扰；前导码(preamble)序列部分，可以由Zadoff-Chu根序列生成；保护间隔(Guarded Time)用于防止本帧数据与下一帧数据之间的干扰。图3示出了一种随机接入序列的结构图示意图。
在步骤S201中，可选的，用户设备可以采用基于竞争的随机接入模式和非竞争的随机接入模式。一个示例中，采用基于竞争的随机接入模式，则还包括步骤S200，卫星向用户设备广播随机接入序列格式信息。可选的，随机接入序列格式信息可承载于SIB2中。用户设备接收卫星广播的随机接入序列格式信息，用户设备基于随机接入序列格式信息生成随机接入序列。可选的，随机接入序列格式信息包括前导格式的索引(index)，用于指示用户设备可采用的随机接入序列的格式信息。可选的，格式信息包括T CP，T SEQ和T GI中至少一项。前导格式的索引与格式信息的对应关系将在下面详细描述。
另一个示例中，采用基于非竞争的随机接入模式，则随机接入序列由卫星分配并指示给用户设备，用户设备生成卫星设备指定的随机接入序列。
可选的，随机接入序列与卫星的轨道高度和卫星的覆盖小区半径相关。
202、用户设备向卫星发送随机接入序列。
该卫星可以为覆盖范围包括用户设备所在的位置的卫星。可选的，该卫星可以为低轨卫星，以低轨卫星作为用户设备发送的信息的接入点，充分利用卫星广域覆盖的能力，为用户提供空中、海洋、以及偏远地区的高效覆盖。
203、卫星接收随机接入序列。
一个示例中，用户设备可以采用与现有的3GPP LTE或5G NR兼容的协议栈向卫星发送所述随机接入序列。相对应地，卫星也采用与现有的3GPP LTE或5G NR兼容的协议栈接收用户设备发送的随机接入序列。进一步的，卫星解析随机接入序列。
为满足卫星通信网络中的超远距离覆盖和超大多普勒频移的问题，随机接入序列的设计需要考虑循环前缀的时间长度T CP，前导序列的时间长度T SEQ和保护间隔的时间长度T GT。T CP，T SEQ和T GT的单位为毫秒(millisecond，ms)。
在一个可能的设计中，为实现与5G NR或LTE的兼容，T SEQ的时长可以为0.8ms的倍数，例如，1.600,2.400ms或，4.800ms等。
在一个可能的设计中，随机接入序列的各个参数满足：T SEQ≥0.8ms；T SEQ≥T CP≥ΔT RTD，T SEQ≥T GT≥ΔT RTD，其中，ΔT RTD为往返时延差。CP时长的设计主要考虑消除覆盖小区内的用户之间RTD时延差ΔT RTD，满足T CP≥ΔT RTD消除了覆盖小区内的用户之间的往返时延RTD时延差ΔT RTD；GT时长的设计主要考虑消除RTD时延差以及本帧的数据对下一帧数据的影响，所以T GT≥ΔT RTD的设计降低了本帧的数据对下一帧数据的影响。在设计中，T CP的长度大致等于T GT，“大致等于”指的是T CP在一定的范围内近似等于T GT，不是绝对意义上的完全相等，可以是实质上的相等，例如T CP≈T GT。
可选的，T CP＝0.684ms或，T CP＝1.828ms，或，T CP＝2.053ms。可选的，T GT＝0.716ms，或，T GT＝0.772ms，或，T GT＝1.147ms，或，T GT＝2.147ms。T CP，T SEQ和T GT的取值可以相互的组合。在一些可能的组合中，T CP，T SEQ，T GT的取值为以下任意一组：
第一组：T CP＝0.684ms,T SEQ＝1.600ms，T GT＝0.716ms；或，
第二组：T CP＝1.828ms,T SEQ＝2.400ms，T GT＝0.772ms；或，
第三组：T CP＝1.828ms,T SEQ＝2.400ms，T GT＝1.772ms；或，
第四组：T CP＝2.053ms,T SEQ＝4.800ms，T GT＝1.147ms；或，
第五组：T CP＝2.053ms,T SEQ＝4.800ms，T GT＝2.147ms。
可选的，随机接入序列的子载波间隔(space of subcarrier,SPS)为5KHz,7.5KHz,15KHz或30KHz。其中，随机接入序列的任一组T CP，T SEQ，T GT参数可以与不同的子载波间隔进行组合。一个示例中，一个前导格式表可以包括随机接入序列的各个参数，如下表1所示，前导格式表中的第一列指示前导格式索引，该索引可以用于指示随机接入序列的格式信息，随机接入的格式信息包括该索引对应的列上的参数。
表1
Figure PCTCN2020080045-appb-000001
Figure PCTCN2020080045-appb-000002
前导格式索引取第一值，第二值或第三值中任一值，对应T CP＝0.684ms，T SEQ＝1.600ms，T GT＝0.716ms；前导格式取第四值，对应，T CP＝1.828ms,T SEQ＝2.400ms，T GT＝0.772ms/1.772ms。前导格式索引取第五值，对应T CP＝2.053ms,T SEQ＝4.800ms，T GT＝1.147ms/2.147ms。可以理解的，前导格式索引的取值与T CP，T SEQ，和T GT这三个的取值的对应关系是可以改变的，不限于本申请实施例所给出的对应关系。
可选的，一个示例中，第一值为4，第二值为5，第三值为6，第四值为7，第五值为8。各前导格式索引例如下表2所示：
表2
Figure PCTCN2020080045-appb-000003
基于上述格式的随机接入序列，其前导序列格式与NR和LTE的相兼容，且从前导格式索引4开始编号，可以与蜂窝网络融合，可以使得相同的用户设备既支持蜂窝网络，又支持卫星网络，能够为用户提供更广的覆盖和更好的用户体验。
一种可能的实现方式中，基于上述前导序列的格式，每种前导格式占用的子帧数，物理随机接入信道(Physical Random Access Channel，PRACH)持续时间，支持的最大小区半径如表3所示：
表3
Figure PCTCN2020080045-appb-000004
由此可见，本申请实施例中的随机接入序列格式，可支持的最大小区半径达到102Km至308Km，可以适应卫星网络超远距离覆盖的特点，可以为用户设备提供更加远距离的覆盖，提升用户设备的服务质量，且采用如上表1至表3的形式，可与5G或LTE蜂窝网络兼容。
一个示例中，随机接入序列的子载波间隔(space of subcarrier,SPS)为5KHz,7.5KHz,15KHz或30KHz。其中，随机接入序列的任一组T CP，T SEQ，T GT参数可以与不同的子载波间隔进行组合。在一些组合方式中，T CP，T SEQ，T GT和子载波间隔可以分别为：
T CP＝0.684ms,T SEQ＝1.600ms，T GT＝0.716ms，所述子载波间隔为5KHz；或，
T CP＝0.684ms,T SEQ＝1.600ms，T GT＝0.716ms，所述子载波间隔为7.5KHz；或，
T CP＝0.684ms,T SEQ＝1.600ms，T GT＝0.716ms，所述子载波间隔为15KHz；或，
T CP＝0.684ms,T SEQ＝1.600ms，T GT＝0.716ms，所述子载波间隔为30KHz；或，
T CP＝1.828ms,T SEQ＝2.400ms，T GT＝0.772ms或T GT＝1.772ms，所述子载波间隔为5KHz；或，
T CP＝1.828ms,T SEQ＝2.400ms，T GT＝0.772ms或T GT＝1.772ms，所述子载波间隔为7.5KHz；或，
T CP＝1.828ms,T SEQ＝2.400ms，T GT＝0.772ms或T GT＝1.772ms，所述子载波间隔为15KHz；或，
T CP＝1.828ms,T SEQ＝2.400ms，T GT＝0.772ms或T GT＝1.772ms，所述子载波间隔为30KHz；或，
T CP＝2.053ms,T SEQ＝4.800ms，T GT＝1.147ms或T GT＝2.147ms，所述子载波间隔为5KHz；或，
T CP＝2.053ms,T SEQ＝4.800ms，T GT＝1.147ms或T GT＝2.147ms，所述子载波间隔为7.5KHz；或，
T CP＝2.053ms,T SEQ＝4.800ms，T GT＝1.147ms或T GT＝2.147ms，所述子载波间隔为15KHz；或，
T CP＝2.053ms,T SEQ＝4.800ms，T GT＝1.147ms或T GT＝2.147ms，所述子载波间隔为30KHz。
在一些组合中，不同前导格式下的子载波间隔可以如表4所示：
表4
Figure PCTCN2020080045-appb-000005
图4示出了本申请实施例提供的随机接入序列的同步成功率的性能分析图。其中，横坐标为信噪比(signal noise ratio,SNR)，纵坐标为同步成功率。在仿真中，本申请实施例采用相同的前导码格式，即相同的CP长度，Sequence长度以及GT长度，对比了在不同频偏(Carrier Frequency Offset，CFO)值为125Hz，625HZ和1KHz的结果。可以看成在载波间隔不变时，如均为1.25KHz，随着频偏的增大，同步成功的概率下降，而在相同的频偏不同的载波间隔的情况下，如频偏均为625Hz时，载波间隔越大，同步成功的概率越大，这说明本申请实施例中采用大的载波间隔可以提升系统的鲁棒性。
一个示例中，前导序列包括：Zadoff-Chu序列，所述Zadoff-Chu序列的时间长度为800us。Zadoff-Chu序列是一种恒幅值，零自相关序列，Zadoff-Chu序列也称为ZC序列，ZC序列的生成的方法为：
Figure PCTCN2020080045-appb-000006
其中的u称为根序列号(Root number)，N CS为ZC序列的长度，且N CS与u互质。ZC序列有如下特点：
Figure PCTCN2020080045-appb-000007
即同一个根序列号生成的两ZC序列不相关,不同根序列号的ZC序列相关值为
Figure PCTCN2020080045-appb-000008
即有：
Figure PCTCN2020080045-appb-000009
可选的，Zadoff-Chu序列的时间长度为800us。现有的5G NR的随机接入序列的子载波间隔为1.25KHz，ZC序列的时长为800us。本申请实施例也采用时长为800us的ZC序列，可实现与5G NR的兼容性。因此，对于本申请实施例提供的多种子载波间隔，需要对ZC序列的映射做相应的调整，以保持ZC序列的长度为800us不变。
一个示例中，以本申请实施例中随机接入序列的子载波间隔为5KHz为例进行说明，如图5所示，左侧为子载波间隔为1.25KHz，时长为800us的ZC序列(LTE/NR中的)的时频域示意图，右侧为子载波间隔为5KHz,时长也为800us的ZC序列(本申请实施例提供的)的时频域示意图。右侧图中的子载波间隔为左侧图中的子载波间隔的4倍，右侧图中的时域的符号持续时间为左侧图中的时域的符号持续时间的1/4。由图5可知，本申请实施例提供的ZC序列占用的频域资源与时隙资源与LTE/NR标准相同。
相类似的，对于随机接入序列的子载波间隔为7.5KHz的情形，ZC序列的符号持续时间是LTE/NR中的ZC序列的符号持续时间的1/6；对于随机接入序列的子载波间隔为15KHz的情形，ZC序列的符号持续时间是LTE/NR中的ZC序列的符号持续时间的1/12；对于随机接入序列的子载波间隔为30KHz的情形，ZC序列的符号持续时间是LTE/NR中的ZC序列的符号持续时间的1/24。
根据上述的介绍可知，可选的。前导码序列的时长T SEQ可以为1600毫秒(us),2400us或4800us。一个示例中，前导码序列的时长T SEQ可以为1600毫秒(us),则前导码序列可以包括一个ZC序列和由所述ZC序列变换得到的序列，其中ZC序列和变换得到的序列的时域时间长度均为800us。为方便描述，记根序号为u的ZC序列为第一序列，记由ZC序列变换得到的序列为第二序列。由所述ZC序列变换得到第二序列的方法包括但不限于以下三种：
第一种方式：第二序列为根序号为u的ZC序列的重复(复制)。
具体的，第一序列为根序号为u的ZC序列，第二序列为ZC序列的重复，第二序列紧跟第一序列，第一序列和第二序列在时域上的持续时间都为800us。其中，第一序列可以采用公式(1)生成，还可以是由公式(1)生成后的序列的循环移位序列。例如图6中第一种方式所示，ZC Seq(root num.u)表示根序号为u的ZC序列。Rep.ZC(root num.u)，表示对根序号(root number)为u的ZC序列做重复，即对同一根序列重复即可，即同一个u值。
第二种方式：第二序列是由所述根序号为u的ZC序列循环移位后的序列。
具体的，第一序列为根序号为u的ZC序列，第二序列为根序号为u的ZC序列的循环移位，其中，第一序列和第二序列在时域上的持续时间都为800us。例如图6中第二种方式所示，Shifted ZC(root num.u)，表示对根序号u的ZC序列做移位，root number为u的ZC 序列表示为x u(n)，x u(n)可以采用上述公式(1)生成，第二序列可以采用如下公式(3)生成，其中k为移位数：
Figure PCTCN2020080045-appb-000010
第三种方式：所述第二序列为根序号为(N CS-u)的ZC序列的共轭序列。
具体的，第一序列为根序号为u的ZC序列，第二序列为根序号为n＝(N CS-u)的ZC序列的共轭序列，其中，第一序列和第二序列在时域上的持续时间都为800us。
一个示例中，前800us的ZC序列(第一序列)的根序号为u，采用上述公式(1)的方式生成，并表示为x u(n)；第二序列记为：Conjugated ZC(root num.u)序列。可以采用如下方式生成第二序列：令v＝N CS-u得到第二序列的新的根序列v,再采用公式(1)生成ZC序列x v(n)，对x v(n)取共轭即conjugate(x v(n))，得到后800us的ZC序列，即第二序列。
相类似的，可参考前述的第一种至第三种方式生成时长为2400us或4800us的前导码序列。例如，前导码序列的时长为2400us,包括第一序列，第二序列和第三序列，其中，第一序列可以为根序号为u的ZC序列，第二序列和第三序列可以采用第一种至第三种的方法生成，此处不再赘述。对于前导序序列时长为4800us的情形，该前导码序列可以包括：第一序列，第二序列，第三序列和第四序列，其中，第一序列可以为根序号为u的ZC序列，第二序列，第三序列和第四序列可以采用第一种至第三种的方法生成，还可以是第二序列由第一序列采用上述第一种至第三种方法生成，再将第一序列和第二序列构成的序列进行变换得到第三序列和第四序列构成的序列。
本申请实施例提供了一种随机接入序列，使得用户设备可以采用卫星(例如，低轨卫星)作为信息的接入点，充分利用卫星广域覆盖的能力，形成对空中、海洋、以及偏远地区的高效覆盖。且该随机接入序列可以适应卫星网络中超远距离的覆盖以及大多普勒频移的特点，可为用户提供更广的覆盖和更好的用户体验。
本申请实施例还提供一种随机接入序列的设计方法，该设计方法考虑到卫星的轨道高度和卫星的广域覆盖能力，设计出能够适应于卫星网络中超远距离覆盖以及大多谱勒频移的特点。可以理解的，上述实施例中涉及的到随机接入序列可以采用本申请实施例提出的方法设计到的，即遵循本身实施例提出的设计准则。
用户设备生成的随机接入序列包括：循环前缀，前导码序列和保护间隔；循环前缀的时间长度为T CP，前导序列的时间长度为T SEQ，保护间隔的时间长度为T GT。
随机接入序列的设计与的卫星的轨道高度和所述卫星的覆盖小区半径相关。
前导序列格式中的T SEQ的计算需要考虑考虑的因素包括如下几个需求：
①序列长度与开销的折中：单个序列必须足够长，以最大化同一Root number下的相互正交的序列的个数，同时，需要在时域上适合若干个子帧，从而保证在大多数的部署中保持物理随机接入信道(Physical Random Access Channel,PRACH)的开销相对较小；
②与最大期望往返时延兼容：前导码的序列的长度，即TSEQ的最小值必须满足小区边缘用户传输时延，即协议支持的最大小区半径小的不同用户之间的时延扩展；
③物理随机接入信道(Physical Random Access Channel,PRACH)和上行共享信道(Physical Uplink Shared Channel,PUSCH)子载波间隔兼容；
为了使得DFT和IDFT的大小NDFT必须为一个整数，即有如下式成立
N DFT＝f sT SEQ＝k，k∈N
这里f s为系统采样间隔，同时需使得前导序列子载波和上行数据传输子载波保持之间的正交性损失减到最低。为满足此要求，需物理上行共享信道(Physical Uplink Shared Channel,PUSCH)数据符号的子载波间隔Δf是物理随机接入信道(Physical Random Access Channel,PRACH)子载波间隔Δf RA的整数倍时，满足这一要求，有
Figure PCTCN2020080045-appb-000011
由此得到T SEQ需满足如下设计标准：
Figure PCTCN2020080045-appb-000012
其中，Δf为系统的子载波间隔，K为正整数。
④覆盖性能
一般来说，较长的序列可以获得较好的覆盖性能，但是较好的覆盖性能要求长的CP与GT以便于低效抵消大的往返时延。可以根据模型或者实测的数据计算出满足一定覆盖范围的T SEQ。
本申请实施例的设计方法中，前导序列的时间长度对应的理论值可表示为：
Figure PCTCN2020080045-appb-000013
其中，N 0为热噪声功率密度；N f为接收机的噪声系数；
Figure PCTCN2020080045-appb-000014
为前导码能量与噪声功率谱密度比，
Figure PCTCN2020080045-appb-000015
P RA为接收功率。一般的，在计算T SEQ(理论)时，N 0＝-174dBm/Hz，N f＝3.5dB；
Figure PCTCN2020080045-appb-000016
的值约16至20dB。在本申请实施例中，接收机指的是卫星的接收机。P RA为卫星的接收功率。
卫星的接收功率可表示为：P RA＝P tx+G tx+G rx-FSL；(公式6)
其中，P tx为发送功率，G tx为发射机的天线增益，G rx为接收机的天线增益，FSL(dB)为自由空间的路径损耗。
可选的，FSL自由空间的路径损耗可以采用多种通信模型计算得到，在一个示例中，自由空间路径损耗FSL(dB)的计算公式为：FSL＝32.4+20log(r)+20log(f)；(公式7)
其中，f为载波频率；为了使得设计得到的随机接入序列可满足卫星覆盖边界的用户设备的随机接入，令r为卫星到卫星的最大小区半径边界处的用户设备之间的距离。当然FSL还 可以采用其他适用于本申请实施例的应用场景的通信模型，例如，采用卫星通信模型。
卫星到卫星的最大小区半径边界处的用户设备之间的距离与卫星的轨道高度和卫星覆盖半径(或最大小区半径处所对应的地心角)有关，覆盖半径也可以称为卫星的最大小区半径或覆盖小区的最大半径，可以由卫星的轨道高度和卫星覆盖半径(或最大小区半径处所对应的地心角)计算得到。r计算的方法和公式包括多种，一种方式，基于卫星的轨道高度和地心角确定r。根据图7，可以采用如下公式计算卫星与用户之间的距离，即：
Figure PCTCN2020080045-appb-000017
其中h为卫星离地面的高度，即卫星的轨道高度，r E为地球半径。在该表达式中，卫星和地面终端之间的地心角为α。其他参数的含义分别为仰角
Figure PCTCN2020080045-appb-000018
半视角β，轨道高度h。
另一种方式，可基于卫星轨道高度和卫星的最大小区半径(即覆盖半径)确定r,此处不再赘述。又一种方式，可基于卫星的最大小区半径边界处的位置信息以及卫星的位置信息，采用勾股定理计算得到r。
利用上述公式5至公式8或公式5至公式8的等效变形或代换，可以计算得到前导序列的时长T SEQ(理论)的值，结合公式4的约束条件即可获取适应于卫星通信系统的，可支持的小区最大覆盖半径大于100Km的实际T SEQ。需要说明的是，T SEQ需满足一定的漏检概率和虚检概率。
除此之外，在CP和GT的设计中，也需要考虑卫星通信场景。一个示例中，循环前缀CP满足，T SEQ≥T CP≥ΔT RTD；一个示例中，T SEQ≥T GT≥ΔT RTD，其中，ΔT RTD为往返时延差。CP的设计主要需考虑消除覆盖小区内的用户之间往返时延(Round Trip Delay,RTD)的时延差，所以CP长度需要满足设计准则1：T SEQ≥T CP≥ΔT RTD；GT的设计主要考虑消除RTD时延差以及本帧的数据对下一帧数据的影响，所以GT长度需要满足设计准则2：T SEQ≥T GT≥ΔT RTD。在设计中，T CP的长度可以大致等于T GT。
基于上述设计方法和设计准则，可以得到多组T SEQ，T CP，T GT。
本申请实施例还验证了设计的前导序列的时长T SEQ与卫星路径损耗之间的关系(如图8左)，以及图前导序列的时长T SEQ与小区最大半径(覆盖最远距离)的仿真图(如图8右)。从上述仿真图可以看成，对于轨道高度700Km的低轨卫星，800us(0.8ms)的序列长度是足够的，如果需要考虑支持低轨300-2000Km的低轨卫星系统，用户设备可发送T SEQ＝1600us(1.6ms)的序列长度的前导码可以支持卫星正常接收，为了保证与现有的LTE/NR协议的兼容性，因此不建议修改序列800us这个基本的序列时间长度设置。
可选的，T SEQ的时长为0.800ms的倍数，例如，1.600ms,2.400ms或，4.800ms等。可选的，T CP＝0.684ms或，T CP＝1.828ms，或，T CP＝2.053ms。可选的，T GT＝0.716ms，或，T GT＝0.772ms，或，T GT＝1.147ms，或，T GT＝2.147ms。可以理解的，T CP，T SEQ和T GT的取值可以相互的组合。
一个示例中，随机接入序列的子载波间隔(space of subcarrier,SPS)为5KHz,7.5KHz,15KHz或30KHz。其中，随机接入序列的任一组T CP，T SEQ，T GT参数可以与不同的子载波间隔进行组合。
在一些组合中，所述随机接入序列满足以下任意一组：
T CP＝0.684ms,T SEQ＝1.600ms，T GT＝0.716ms，所述子载波间隔为5KHz；或，
T CP＝0.684ms,T SEQ＝1.600ms，T GT＝0.716ms，所述子载波间隔为7.5KHz；或，
T CP＝0.684ms,T SEQ＝1.600ms，T GT＝0.716ms，所述子载波间隔为15KHz；或，
T CP＝1.828ms,T SEQ＝2.400ms，T GT＝0.772ms或T GT＝1.772ms，所述子载波间隔为7.5KHz；或，
T CP＝1.828ms,T SEQ＝2.400ms，T GT＝0.772ms或T GT＝1.772ms，所述子载波间隔为15KHz；或，
T CP＝1.828ms,T SEQ＝2.400ms，T GT＝0.772ms或T GT＝1.772ms，所述子载波间隔为30KHz；或，
T CP＝2.053ms,T SEQ＝4.800ms，T GT＝1.147ms或T GT＝2.147ms，所述子载波间隔为7.5KHz；或，
T CP＝2.053ms,T SEQ＝4.800ms，T GT＝1.147ms或T GT＝2.147ms，所述子载波间隔为15KHz；或，
T CP＝2.053ms,T SEQ＝4.800ms，T GT＝1.147ms或T GT＝2.147ms，所述子载波间隔为30KHz。
选取多种组合中的一部分组合即可构成如表1至表4中的随机接入序列格式。
本申请实施例提供了一种随机接入序列，使得用户设备可以采用卫星(例如，低轨卫星)作为信息的接入点，充分利用卫星广域覆盖的能力，形成对空中、海洋、以及偏远地区的高效覆盖。且该随机接入序列可以适应卫星网络中超远距离的覆盖以及大多普勒频移的特点，可为用户提供更广的覆盖和更好的用户体验。
本申请实施例中，用户设备和/或卫星设备可以采用多种方式生成随机接入序列，可选的，T SEQ的时长为0.800ms的倍数，例如，1.600ms,2.400ms或，4.800ms等。可选的，T CP＝0.684ms或，T CP＝1.828ms，或，T CP＝2.053ms。可选的，T GT＝0.716ms，或，T GT＝0.772ms，或，T GT＝1.147ms，或，T GT＝2.147ms。可选的，随机接入序列的子载波间隔(space of subcarrier,SPS)为5KHz,7.5KHz,15KHz或30KHz。
用户设备和卫星可以采用如下多种方式交互随机接入序列的格式信息，包括但不限于如下几种方式：
在一种实施方式中，用户设备和卫星设备双方都存储随机接入序列格式表，该随机接入序列格式表格中包括：格式索引对应的随机接入序列的格式信息，该格式信息包括循环前缀的时间长度T CP，前导序列的时间长度T SEQ和保护间隔的时间长度T GT，可选的，还包括格式索引对应的子载波间隔。
T CP，T SEQ和T GT的取值，以及子载波间隔的取值可以相互的组合，构成多个组合。随机接入格式表格包括：T CP，T SEQ和T GT以及子载波间隔的构成的多个组合中的一个或多个。例如，上述表1至上述表4。
第一种方式中，该随机接入序列格式表格可以以协议约定的方式，用户设备和卫星设备都存储随机接入序列格式表格；第二种方式中，该随机接入序列格式表格可以由卫星作为系统参数下发给用户设备，用户设备接收之后存储该随机接入序列格式表格。基于上述两种方式，在步骤S200中，卫星设备广播的随机接入格式信息可包括：格式索引。因此接收到格式索引的用户设备即可查表确定该格式索引所对应的随机接入序列的格式信息。基于第一种实施方式，可有效的节省信令开销，提升传输的效率。
在第二种实施方式中，在步骤S200中，卫星设备发送的随机接入序列格式信息包括要分 配给该用户设备的一项随机接入序列的格式信息，以及，该用户设备的标识，该用户设备的标识可报告该用户设备的MAC地址或IP地址，或该卫星该给用户设备分配的卫星网络地址等。该方法可应用于于仅卫星设备存储上述随机接入序列格式表的情形，还可以应用于用户设备和卫星设备都存储上述随机接入序列格式表的情形。基于第二种实施方式，节省用户设备的存储空间，提升传输的鲁棒性。
在第三种实施方式中，用户设备不存储随机接入序列格式表格，卫星设备可以存储也可以不存储随机接入序列格式表格。随机接入序列格式信息包括卫星的星历信息；一个示例中，星历信息可包括卫星的位置信息(轨道高度，经纬度等)和卫星的运行周期。用户设备可以基于GPS卫星或地面基站获取自身的GPS位置信息。用户设备利用卫星的位置信息和自身的位置信息，基于上述实施例所涉及的设计准则，例如，公式4至公式7，或其等效的变形形式计算得到随机接入序列中的各参数。可选的，公式4至公式8可存储至用户设备中。基于第三种实施方式，可节省用户设备的存储空间，且用户设备可根据卫星的轨道高度实时灵活调整随机接入序列的格式，灵活性提高。
在第四种实施方式中，用户设备和卫星设备都不存储随机接入序列格式表格，卫星设备可基于卫星的轨道高度和卫星的覆盖范围对应的小区半径，采用公式4至公式8或其等效的变形或代换形式，以及设计准则，计算得到随机接入序列中的各参数，并将计算得到的各参数下发给用户设备。基于第四种实施方式，可节省用户设备以及卫星的存储空间，且卫星根据卫星的轨道高度实时灵活调整随机接入序列的格式，计算速度快，灵活性提高。
进一步的，在步骤S201中，基于获取到的随机接入序列的格式信息，生成随机接入序列，并向卫星发送该随机接入序列。
本申请实施例提供了一种随机接入序列，其鲁棒性更强使得用户设备可以采用卫星(例如，低轨卫星)作为信息的接入点，充分利用卫星广域覆盖的能力，形成对空中、海洋、以及偏远地区的高效覆盖。且该随机接入序列可以适应卫星网络中超远距离的覆盖以及大多普勒频移的特点，可为用户提供更广的覆盖和更好的用户体验。
本申请实施例还提供一种时间提前量(Time Advance,TA)的指示方法。如图9所示，包括：
S901，卫星发送时间提前量(Time Advance,TA)的初始调整值信息；其中，所述初始调整值信息用于向用户设备指示时间提前量的初始调整值。
S902，用户设备接收时间提前量初始调整值信息；
用户设备可基于初始调整值实现该时间提前量的初步调整。
可选的，S903，卫星发送时间提前量的跟踪值信息，跟踪值信息用于向用户设备指示时间提前量的跟踪值。一个示例中，在卫星发现用户设备与卫星不同步的情况下，卫星可以发送时间提前量的跟踪值信息，用于用户设备进行时间提前量的精调，实现用户设备与卫星的同步。
可选的，S904，用户设备接收时间提前量的跟踪值信息。
用户设备可基于跟踪值信息实现时间提前量的细微调整。
在本申请实施例中，初始调整值信息与跟踪值信息可以采用多种不同的承载方式：可选的，初始调整值信息承载于随机接入信道响应(RACH Response，RAR)中的时间提前量TA控制(Time Advance Command)字段中。一个示例中，随机接入信道响应遵循LTE标准，初始调 整值信息承载于LTE RAR的TA控制字段中；另一个示例中，随机接入信道响应遵循5G NR标准，初始调整值信息承载于NR RAR的TA控制字段中。采用前述两种方式，可实现与蜂窝网络的兼容，降低用户设备设计的复杂度。
TA初始调整值的最小时间单位是采样时间(sampling time，TS)。以LTE为例，TS1＝1/(2048*15000)＝32.55ns(纳秒)。LTE协议规定，TA的调整量是以16 TS为步长的，则TA的调整单位是16 TS＝0.5208us。可选的，本申请实施例中的初始调整值信息采用多个比特表示初始调整值，多个比特的比特数大于12，或大于11。例如，初始调整值信息包括16个比特。
可选的，跟踪值信息承载于媒体访问控制元素的时间提前量(TA)字段中。跟踪值最小时间单位是TS2(sampling time，TS)，以LTE/NR为例，TS2＝1/(2048*15000)＝32.55ns，跟踪值的调整量的步长为16倍的TS2，TA跟踪值的调整范围为(-16.7us,16.7us)。可选的，跟踪值信息可以包括多个比特标示跟踪值，多个比特的比特数大于6。例如，跟踪值信息包括8比特。
接收到TA调整信息的用户设备可以依据初始值对时间提前量进行粗粒度的初调，进一步基于跟踪值进行细粒度的跟踪调整。
一个实施方式中，用户设备可采用如下TA调整公式进行调整：
N TA,new＝N TA,old+(T A-127)×16
其中，N TA,new为最新的timing advance调整值，N TA,old为最近一次timing advance的调整值，T A为用户设备收到新的Timing Advance Command而得到的跟踪值。
本申请实施例设计了适用于卫星通信系统的时间提前量调整方法，且该时间提前量的指示与LTE或5G NR的时间提前量指示兼容，既可以为用户设备提供更大范围的覆盖，还可以简化卫星通信系统的设计，实现蜂窝网络与卫星网络的融合。
本申请实施例提供了一种通信装置1000，该通信装置1000可应用于用户设备端，可以用于实现上述实施例中涉及用户设备的方法和步骤。用户设备可以是如图1所示的用户设备102，例如，用户终端、卫星终端、蜂窝终端、地面站、蜂窝基站和接入点等。该通信装置可以是用户设备，还可以是用户设备内的芯片。
参见图10，该通信装置1000包括：处理模块1001，通信模块1002。
处理模块1001，可以用于生成随机接入序列，所述随机接入序列包括：循环前缀、前导码序列和保护间隔；所述循环前缀的时间长度为T CP，所述前导码序列的时间长度为T SEQ，所述保护间隔的时间长度为T GT。处理模块1001还可以用于解析TA初始调整值信息和TA跟踪值信息。例如用于实现步骤S201，或者，用于控制通信模块1002实现步骤S202。
通信模块1002，用于发送随机接入序列。一个示例中，该通信模块1002可以包括：蜂窝通信模块和卫星通信模块，其中，蜂窝通信模块使得通信装置1000可以采用无线通信协议(例如LTE或5G NR协议)与蜂窝网络进行通信，卫星通信模块可以采用与LTE或5G NR协议相兼容的协议与卫星网络中的卫星进行通信。通信模块1002还包括接收模块和发送模块。通信模块1002还可以用于发送TA初始调制值和跟踪值。例如，用于实现步骤S202中的随机接入序列，或，用于接收步骤S901或步骤S903中的时间提前量调整信息。
本实施例中，T CP、T SEQ和T GT以及子载波间隔的可参考前面实施例的说明，此处不再赘述。
本申请实施例还提供一种通信装置1100。该通信装置1100可应用于用户设备端，可以用于实现上述实施例中涉及用户设备的方法和步骤。用户设备可以是如图1所示的位于地面段的通信装置，例如，用户终端、卫星终端、蜂窝终端、地面站、蜂窝基站和接入点等。该通信装置可以是用户设备，还可以是用户设备内的芯片。
一个示例中，该用户设备为一种终端设备。图11示出了上述实施例中所涉及的用户设备的一种可能的设计结构的简化示意图。所述用户设备包括发射器1101，接收器1102，控制器/处理器1103，存储器1104和调制解调处理器1105。
发射器1101调节(例如，模拟转换、滤波、放大和上变频等)该输出采样并生成上行链路信号，该上行链路信号经由天线发射给上述实施例中所述的卫星。在下行链路上，天线接收上述实施例中卫星发射的下行链路信号。接收器1102调节(例如，滤波、放大、下变频以及数字化等)从天线接收的信号并提供输入采样。在调制解调处理器1105中，编码器1106接收要在链路上发送的业务数据和信令消息，并对业务数据和信令消息进行处理(例如，格式化、编码和交织)。调制器1107进一步处理(例如，符号映射和调制)编码后的业务数据和信令消息并提供输出采样。解调器11011处理(例如，解调)该输入采样并提供符号估计。解码器1108处理(例如，解交织和解码)该符号估计并提供发送给用户设备的已解码的数据和信令消息。编码器1106、调制器1107、解调器11011和解码器1108可以由合成的调制解调处理器1105来实现。
控制器/处理器1103对用户设备的动作进行控制管理，用于执行上述实施例中由用户设备进行的处理。
存储器1103用于存储用户设备的程序代码和数据。
可以理解的是，图11仅仅示出了用户设备的简化设计。在实际应用中，用户设备可以包含任意数量的发射器，接收器，处理器，控制器，存储器，通信单元等，而所有可以实现本申请的用户设备都在本发明的保护范围之内。
需要说明的是，T CP、T SEQ和T GT以及子载波间隔的可参考前面实施例的说明，此处不再赘述。
本申请实施例提供了一种通信装置1200，该通信装置1200可应用于卫星端，可以用于实现上述实施例中涉及卫星的方法和步骤。通信装置可以是如图1所示的卫星121。该通信装置还可以是卫星内的芯片。参见图12，该通信装置1200包括：处理模块1201，发送模块1202，可选的，还包括接收模块1203。
处理模块1201，可以解析接收到的随机接入序列。可选的，处理模块1201还可以用于生成TA初始值信息和TA调整值信息。
接收模块1202，用于接收用户设备发送的随机接入序列。例如，接收模块用于实现S203。
发送模块1203，用于向用户设备发送TA初始值信息和TA调整值信息。例如，发送模块用于实现S902。
本实施例中，T CP、T SEQ和T GT以及子载波间隔的可参考前面实施例的说明，此处不再赘述。
需要说明的是，上述实施例中“发送”的动作也可以指的是“提供”或“输出”；上述“接收”的动作也可以指的是“获取”或“输入”。
本申请实施例还提供一种计算机存储介质，该计算机可读存储介质中存储有指令，所述指令可以由处理电路上的一个或多个处理器执行。当其在计算机上运行时，使得计算机执行上述各方面所述的方法。
本申请实施例还提供了一种芯片系统，该芯片系统包括处理器，用于支持分布式单元、集中式单元、以及卫星或用户设备以实现上述实施例中所涉及的功能，例如生成或处理上述方法中所涉及的数据和/或信息。在一种可能的设计中，所述芯片系统还可以包括存储器，所述存储器，用于保存分布式单元、集中式单元以及卫星或用户设备必要的程序指令和数据。该芯片系统，可以由芯片构成，也可以包含芯片和其他分立器件。
本申请实施例还提供了一种芯片，包括处理器，用于从存储器中调用并运行所述存储器中存储的指令，使得安装有所述芯片的通信设备执行上述各示例中的方法。
本申请实施例还提供另一种芯片，包括：输入接口、输出接口、处理器和存储器，所述输入接口、输出接口、所述处理器以及所述存储器之间通过内部连接通路相连，所述处理器用于执行所述存储器中的代码，当所述代码被执行时，所述处理器用于执行上述各示例中的方法。
本申请实施例还提供另一种芯片，该芯片可以成为用户设备或卫星的一部分，该芯片包括：输入接口、输出接口和电路，所述输入接口、所述输出接口与所述电路之间通过内部连接通路相连，所述电路用于执行上述各示例中的方法。
本申请实施例还提供了一种处理器，用于与存储器耦合，用于执行上述各实施例中任一实施例中涉及卫星或用户设备的方法和功能。
本申请实施例还提供了一种包含指令的计算机程序产品，其在计算机上运行时，使得计算机执行上述各实施例中任一实施例中涉及卫星或用户设备的方法和功能。
本申请实施例还提供一种通信系统，该系统包括上述实施例中涉及的卫星和至少一个用户设备。
本申请实施例还提供一种装置，用于实现上述各实施例中的方法。
在上述实施例中，可以全部或部分地通过软件、硬件、固件或者其任意组合来实现。当使用软件实现时，可以全部或部分地以计算机程序产品的形式实现。所述计算机程序产品包括一个或多个计算机指令。在计算机上加载和执行所述计算机程序指令时，全部或部分地产生按照本申请所述的流程或功能。所述计算机可以是通用计算机、专用计算机、计算机网络、或者其他可编程装置。所述计算机指令可以存储在计算机可读存储介质中，或者从一个计算机可读存储介质向另一个计算机可读存储介质传输，例如，所述计算机指令可以从一个网站站点、计算机、服务器或数据中心通过有线(例如同轴电缆、光纤、数字用户线)或无线(例如红外、无线、微波等)方式向另一个网站站点、计算机、服务器或数据中心进行传输。所述计算机可读存储介质可以是计算机能够存取的任何可用介质或者是包含一个或多个可用介质集成的服务器、数据中心等数据存储设备。所述可用介质可以是磁性介质，(例如，软盘、硬盘、磁带)、光介质(例如，DVD)、或者半导体介质(例如固态硬盘Solid State Disk)等。

Claims (24)

  1. 一种随机接入方法，其特征在于，包括：
    用户设备生成随机接入序列，所述随机接入序列包括：循环前缀、前导码序列和保护间隔；所述循环前缀的时间长度为T CP，所述前导码序列的时间长度为T SEQ，所述保护间隔的时间长度为T GT；
    所述随机接入序列用于所述用户设备接入所述卫星，所述随机接入序列支持的最大小区半径大于100Km；
    所述用户设备发送所述随机接入序列。
  2. 一种随机接入方法，其特征在于，包括：
    卫星接收来自用户设备随机接入序列，所述随机接入序列包括：循环前缀、前导码序列和保护间隔；所述循环前缀的时间长度为T CP，所述前导码序列的时间长度为T SEQ，所述保护间隔的时间长度为T GT；所述随机接入序列用于所述用户设备接入所述卫星，所述随机接入序列支持的最大小区半径大于100Km；
    所述卫星解析所述随机接入序列。
  3. 根据权1或2所述的方法，其特征在于，所述随机接入序列的子载波间隔大于等于1.25KHz。
  4. 根据权利要求1至3中任一项所述的方法，其特征在于，T SEQ≥0.8ms，T SEQ≥T CP≥ΔT RTD，T SEQ≥T GT≥ΔT RTD，其中，ΔT RTD为往返时延差。
    GT和CP大致相同。
  5. 根据权利要求1至4中任一项所述的方法，其特征在于，
    所述随机接入序列的子载波间隔为5KHz,7.5KHz,15KHz或30KHz。
  6. 根据权利要求1至5中任一项所述的方法，其特征在于，所述随机接入序列满足以下任一项：
    T CP＝0.684ms,T SEQ＝1.600ms，T GT＝0.716ms；或，
    T CP＝1.828ms,T SEQ＝2.400ms，T GT＝0.772ms；或，
    T CP＝1.828ms,T SEQ＝2.400ms，T GT＝1.772ms；或，
    T CP＝2.053ms,T SEQ＝4.800ms，T GT＝1.147ms；或，
    T CP＝2.053ms,T SEQ＝4.800ms，T GT＝2.147ms。
  7. 根据权利1至6中任一项所述的方法，其特征在于，所述随机接入序列与所述卫星的轨道高度和卫星的覆盖小区半径相关。
  8. 根据权利要求1至7中任一项所述的方法，其特征在于，T SEQ＝1.600ms，所述前导码序列包括：第一序列和第二序列，所述第一序列为根序号为u的Zadoff-Chu序列，所述第一序列和所述第二序列的时间长度为0.8ms；其中，
    所述第二序列为所述根序号为u的Zadoff-Chu序列的重复；或，
    所述第二序列为所述根序号为u的Zadoff-Chu序列循环移位后的序列；或，
    所述第二序列为根序号为Ncs-u的Zadoff-Chu序列的共轭序列，其中Ncs为前导序列的长度。
  9. 根据权1所述的方法，其特征在于，所述方法还包括：
    接收卫星设备广播随机接入序列格式信息；所述随机接入序列格式信息用于指示所述随机接入序列的T CP，T SEQ和T GT；
    所述用户设备生成随机接入序列，包括，所述用户设备基于所述随机接入序列分配信息生成所述随机接入序列。
  10. 根据权利要求2所述的方法，其特征在于，所述方法还包括：
    广播随机接入序列格式信息，所述随机接入序列格式信息用于指示所述随机接入序列的T CP，T SEQ和T GT。
  11. 一种随机接入序列的通信装置，其特征在于，应用于用户设备，所述通信装置包括：
    处理模块，用于生成随机接入序列，所述随机接入序列包括：循环前缀、前导码序列和保护间隔；所述循环前缀的时间长度为T CP，所述前导码序列的时间长度为T SEQ，所述保护间隔的时间长度为T GT；
    所述随机接入序列用于所述用户设备接入卫星，所述随机接入序列支持的最大小区半径大于100Km；
    通信模块，用于向所述卫星发送所述随机接入序列。
  12. 一种随机接入序列的通信装置，其特征在于，应用于卫星，所述通信装置包括：
    接收模块，用于接收来自用户设备的随机接入序列，所述随机接入序列包括：循环前缀、前导码序列和保护间隔；所述循环前缀的时间长度为T CP，所述前导码序列的时间长度为T SEQ，所述保护间隔的时间长度为T GT；所述随机接入序列用于所述用户设备接入所述卫星；
    所述随机接入序列支持的最大小区半径大于100Km；
    处理模块，用于解析所述随机接入序列。
  13. 根据权11或12所述的通信装置，其特征在于，所述随机接入序列的子载波间隔大于等于1.25KHz。
  14. 根据权利要求11至13中任一项所述的通信装置，其特征在于，T SEQ≥0.8ms，T SEQ≥T CP≥ΔT RTD，T SEQ≥T GT≥ΔT RTD。
    GT和CP大致相同。
  15. 根据权利要求11至14中任一项所述的通信装置，其特征在于，
    所述随机接入序列的子载波间隔为5KHz,7.5KHz,15KHz或30KHz。
  16. 根据权利要求11至15中任一项所述的通信装置，其特征在于，所述随机接入序列满足以下任一项：
    T CP＝0.684ms,T SEQ＝1.600ms，T GT＝0.716ms；或，
    T CP＝1.828ms,T SEQ＝2.400ms，T GT＝0.772ms；或，
    T CP＝1.828ms,T SEQ＝2.400ms，T GT＝1.772ms；或，
    T CP＝2.053ms,T SEQ＝4.800ms，T GT＝1.147ms；或，
    T CP＝2.053ms,T SEQ＝4.800ms，T GT＝2.147ms。
  17. 根据权利11至16中任一项所述的通信装置，其特征在于，所述随机接入序列与所述卫星的轨道高度和卫星的覆盖小区半径相关。
  18. 根据权利要求11至17中任一项所述的通信装置，其特征在于，T SEQ＝1.600ms，所述前导码序列包括：第一序列和第二序列，所述第一序列为根序号为u的Zadoff-Chu序列，所述第一序列和所述第二序列的时间长度为800us；其中，
    所述第二序列为所述根序号为u的Zadoff-Chu序列的重复；或，
    所述第二序列为所述根序号为u的Zadoff-Chu序列循环移位后的序列；或，
    所述第二序列为根序号为Ncs-u的Zadoff-Chu序列的共轭序列，其中Ncs为前导序列的长度。
  19. 根据权11所述的通信装置，其特征在于：
    所述通信模块，还用于接收卫星设备广播随机接入序列格式信息；所述随机接入序列格式信息用于指示所述随机接入序列的T CP，T SEQ和T GT；
    所述处理模块具体用于基于所述随机接入序列分配信息生成所述随机接入序列。
  20. 根据权利要求12所述的通信装置，其特征在于，所述通信装置还包括：
    所述发送模块，还用于广播随机接入序列格式信息，所述随机接入序列格式信息用于指示所述随机接入序列的T CP，T SEQ和T GT。
  21. 一种装置用于执行权利要求1至10中任一项所述的方法。
  22. 一种装置，其特征在于，包括：处理器用于与存储器耦合，所述存储器用于存储指令，当所述指令被所述处理器运行时，使得所述装置执行权利要求1至10中任一项所述的方法。
  23. 一种计算机可读存储介质，所述计算机存储介质中存储有程序代码，该程序代码用于包括用于执行权利要求1至10中任一项所述的方法的指令。
  24. 一种计算机程序产品，其在计算机上运行时，使得计算机执行权利要求1至10中任一项所述的方法。
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CN112566094B (zh) * 2020-12-04 2022-11-04 展讯通信（上海）有限公司 终端设备及其随机接入方法、计算机可读存储介质
CN112929104B (zh) * 2021-01-02 2021-09-21 军事科学院系统工程研究院网络信息研究所 高低轨同频共存卫星通信系统的共线干扰估计方法
CN115379510A (zh) * 2021-05-18 2022-11-22 华为技术有限公司 信号发送、接收方法及装置
CN114095112B (zh) * 2021-10-12 2023-09-15 北京长焜科技有限公司 一种基于5g nr无线通信技术的长距离接入方法
CN114650611B (zh) * 2022-03-21 2023-03-17 南京林业大学 一种基于zc序列的5g低轨卫星随机接入信号设计方法

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101854729A (zh) * 2010-03-30 2010-10-06 中国人民解放军信息工程大学 一种卫星通信系统的随机接入方法
WO2011017281A1 (en) * 2009-08-06 2011-02-10 Qualcomm Incorporated Dynamic selection of random access channel configurations
CN103346829A (zh) * 2013-07-01 2013-10-09 北京大学 兼容lte模式卫星通信初始随机接入两步时延测量方法
CN105915315A (zh) * 2016-04-15 2016-08-31 哈尔滨工业大学 天地一体化系统面向随机接入的lte帧结构改进方法及获得的lte帧结构

Family Cites Families (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR102039065B1 (ko) * 2012-05-08 2019-10-31 한국전자통신연구원 큰 셀 반경을 가지는 이동 통신 시스템에서의 랜덤 액세스 방법 및 랜덤 액세스 채널 구조

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2011017281A1 (en) * 2009-08-06 2011-02-10 Qualcomm Incorporated Dynamic selection of random access channel configurations
CN101854729A (zh) * 2010-03-30 2010-10-06 中国人民解放军信息工程大学 一种卫星通信系统的随机接入方法
CN103346829A (zh) * 2013-07-01 2013-10-09 北京大学 兼容lte模式卫星通信初始随机接入两步时延测量方法
CN105915315A (zh) * 2016-04-15 2016-08-31 哈尔滨工业大学 天地一体化系统面向随机接入的lte帧结构改进方法及获得的lte帧结构

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
DISH NETWORK ET AL.: "Satellite Aspects-Forward Compatibility Consideration for Random Access Preamble Format", 3GPP TSG RAN WG1 MEETING NR AH R1-1700700, 9 January 2017 (2017-01-09), DOI: 20200602172152X *

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