GPS ICD_200H更新历史与关键改动：从1983年至2011年

需积分: 9 178 浏览量更新于2024-07-19 收藏 1.87MB PDF 举报

《最新版GPS ICD_200H》文档是全球定位系统（GPS）接口控制文档（Interface Control Document, ICD）的重要参考资料，其历史版本更新记录反映了GPS技术的演进和发展。这份文档自1983年发布初始版本以来，历经多次修订，旨在确保与GPS卫星信号接收设备的兼容性和功能一致性。以下是关键的版本变更点： 1. **1983年A版（InitialRelease）**: 初次发布，包含了IRN-200系列的最早几个修正文档，奠定了基础规范。 2. **1984年B版**：引入了IRN-200A-001A，可能涉及软件或技术改进。 3. **1987年C版**：加入了IRN-200B系列的多个版本，反映了更深层次的技术集成和升级。 4. **1993年C版**：转换成Microsoft Word 6.0格式，适应了当时的技术环境。 5. **1996年C版**：将分发状态改为公开发布，促进了更广泛的共享和应用。 6. **1997年D版**：这一版本至关重要，引入了IRN-200C系列的修订，包括ICD-GPS-200更名为IS-GPS-200，增加了对Improved Clock and Ephemeris (ICE)消息的要求，以及L2C信号处理的规格更新。 7. **2004年**：发布IRN-200D-001，扩展了PRN序列，并可能对卫星导航性能有进一步优化。 8. **2006年**：随着GPS IIIA的整合，文档内容与新功能相适应。 9. **2010年**：包含SE&ITechPubs的文档，如RFC16B关于伪随机噪声（PRN）扩展，加强了信号的精确性。 10. **2011年至2012年**：进一步发布了关于公共文档管理、术语定义和用户范围准确性等关键领域的RFC文档。这些修订不仅展示了GPS技术在定位精度、数据传输、信号处理等方面的发展，也体现了行业标准和规范的不断完善。《最新版GPS ICD_200H》对于GPS接收设备制造商、导航系统开发者以及任何与GPS技术相关的研究人员来说，都是至关重要的学习和参考资源。通过追踪这些历史修订，我们可以看到GPS技术如何在保持一致性的同时，不断适应新的需求和挑战。

3.2.1 Ranging Codes.

Three PRN ranging codes are transmitted: the precision (P) code which is the principal

navigation ranging code; the Y-code, used in place of the P-code whenever the anti-spoofing (A-

S) mode of operation is activated; and the coarse/acquisition (C/A) code which is used for

acquisition of the P (or Y) code (denoted as P(Y)) and as a civil ranging signal. Code-division-

multiple-access techniques allow differentiating between the SVs even though they may transmit

at the same frequencies. The SVs will transmit intentionally "incorrect" versions of the C/A and

the P(Y) codes where needed to protect the users from receiving and utilizing anomalous

navigation signals. These two "incorrect" codes are termed non-standard C/A (NSC) and non-

standard Y (NSY) codes.

For Block IIR-M, IIF, and subsequent blocks of SVs, two additional PRN ranging codes are

transmitted. They are the L2 civil-moderate (L2 CM) code and the L2 civil-long (L2 CL) code.

The SVs will transmit intentionally "incorrect" versions of the L2 CM and L2 CL codes where

needed to protect the users from receiving and utilizing anomalous navigation signals. These

"incorrect" codes are termed non-standard L2 CM (NSCM) and non-standard L2 CL (NSCL)

codes. The SVs shall also be capable of initiating and terminating the broadcast of NSCM

and/or NSCL code(s) independently of each other, in response to CS command.

Users shall only use non-dummy satellites as defined via current broadcast almanac. See Section

20.3.3.5.1.2 and/or Section 40.3.3.5.1.2 for the definition of information about dummy satellites

in the almanac.

3.2.1.1 P-Code.

The PRN P-code for SV ID number i, for i = 1 to 37, is a ranging code, P

(t), of 7 days in length

at a chipping rate of 10.23 Mbps. The 7 day sequence is the modulo-2 sum of two sub-sequences

referred to as X1 and X2

; their lengths are 15,345,000 chips and 15,345,037 chips, respectively.

The X2

sequence is an X2 sequence selectively delayed by 1 to 37 chips thereby allowing the

basic code generation technique to produce a set of 37 mutually exclusive P-code sequences of 7

days in length. Assignment of these code phase segments by SV ID number is given in Table 3-

Ia. (NOTE: previous versions of this document reserved PRNs 33 through 37 for other uses.

Due to increased system capability, PRNs 33 through 37 are being redesignated to allow for use

by SVs.)

An initial almanac collected from P(Y)-code in the upper PRNs must be obtained from PRNs 35,

36, or 38 through 63.

3.2.1.1.1 Expanded P-Code (GPS III).

An expanded set of 26 P-code PRN sequences are generated by circularly shifting 26 of the

original 37 sequences (over one week) by an amount corresponding to 1 day. These expanded

sequences are therefore time shifted (i.e. offset) versions of 26 of the original sequences.

Assignment of these expanded code phase segments by SV ID number is given in Table 3-Ib.

3 IS-GPS-200H

24 Sep 2013

Additional PRN P-code sequences with assigned PRN numbers are provided in Section 6.3.6,

Table 6-I.

3.2.1.2 Y-Code.

The PRN Y-code is used in place of the P-code when the A-S mode of operation is activated.

3.2.1.3 C/A-Code.

The PRN C/A-Code for SV ID number i is a Gold code, G

(t), of 1 millisecond in length at a

chipping rate of 1023 Kbps. The G

(t) sequence is a linear pattern generated by the modulo-2

addition of two sub-sequences, G1 and G2

, each of which is a 1023 chip long linear pattern.

The epochs of the Gold code are synchronized with the X1 epochs of the P-code. As shown in

Table 3-Ia, the G2

sequence is a G2 sequence selectively delayed by pre-assigned number of

chips, thereby generating a set of different C/A-codes. Assignment of these by GPS PRN signal

number are given in Table 3-Ia and Table 3-Ib.

An initial almanac collected from C/A Code in the upper PRNs must be obtained from PRNs 35,

36, or 38 through 63.

CS will prevent the simultaneous transmission of PRNs 34 and 37 of C/A code.

3.2.1.3.1 Expanded C/A Code (GPS III)

An expanded set of 26 C/A-code PRN sequences are identified in Table 3-Ib using “G2 Delay”

and “Initial G2 Setting” which is not the same as the method used in Table 3-Ia. The two-tap

coder implementation method referenced and used in Table 3-Ia is not used in Table 3-Ib due to

its limitation in generating C/A-code sequences. The “G2 Delay” specified in Table 3-Ib may be

accomplished by using the “Initial G2 Setting” as the initialization vector for the G2 shift register

of Figure 3-9. Assignment of these expanded code phase segments by SV ID number is given in

Table 3-Ib. Additional PRN C/A-code sequences with assigned PRN numbers are provided in

Section 6.3.6.1, Table 6-I.

3.2.1.4 L2 CM-Code (IIR-M, IIF, and subsequent blocks).

The PRN L2 CM-code for SV ID number i is a ranging code, C

M,i

(t), which is 20 milliseconds in

length at a chipping rate of 511.5 Kbps. The epochs of the L2 CM-code are synchronized with

the X1 epochs of the P-code. The C

M,i

(t) sequence is a linear pattern which is short cycled every

count of 10230 chips by resetting with a specified initial state. Assignment of initial states by

GPS PRN signal number is given in Table 3-IIa.

3.2.1.4.1 Expanded L2 CM Code (GPS III and subsequent blocks).

An expanded set of 26 L2 CM-Code PRN sequences are identified with assignment of initial

states by SV ID number in Table 3-IIb. Additional PRN L2 CM-code sequence pairs are

provided in Section 6.3.6.3, Table 6-II.

4 IS-GPS-200H

24 Sep 2013

剩余225页未读，继续阅读

Sigma_i

粉丝: 3
资源: 1

GPS ICD_200H更新历史与关键改动：从1983年至2011年

GPS L5空间接口ICD文档

ICD-GPS-200C.rar_ICD GPS_ICD-GPS 下载_icd-180_icd-gps-200c_icd-gps

gps icd.zip_GPS_GPS icd_GPS simulation_ICD_ca code

ICD-GPS-705-L5-rev2.rar_GPS_GPS L5_GPS icd_ICD_GPS_L5

icd2.rar_ICD_icd icd2_icd2_pic icd_pic programmer

GLONASS_ICD.rar_GLONASS_ICD_ICD GLONASS_glonass_glonass icd_site

GNSS_ICD_Document_irnss_.icd_GNSS_QZSS_

最新Galileo_OS_SIS_ICD_v2.0.pdf

ICD.rar_ICD_ICDDEMO BOARD_Icd语言_icddemo boa_mplab

nari-icd.zip_61850icd_61850南瑞_icd 模型_南瑞61850_南瑞icd文件

最新资源