Student of Donetsk National Technical University Medvediev Kyrylo

Medvediev Kyrylo

Computer Science and Technologies Faculty
Department of computer engineering
Speciality: Computer systems and networks
Theme of master's work:
Development and research of the structure of navigation system that based on FPGA-technology Research director: Yury Zinchenko

Abstract

"Development and research of the structure of navigation system"

that based on FPGA-technology

Author: Medvediev Kyrylo

Preface

Modern microelectronic devices presently are being implemented in all spheres of human activity. Miniaturization, reduced power consumption and cheap components make them available for mass use [3].
Navigation industry has not remained on the sidelines of progress. For a long time civilians had access to only one signal of global navigation satellite system (GNSS) [4]. In the next few years, there will be a steady increase in the number of such signals. The amount of "hunters for the others wealth" has always been enough. Navigational tools can easily perform the role of security systems and alarms, so will be needed to ensure the safety of specific object and each person on the planet. Navigational tools can easily perform the role of security systems and alarms, so will be needed to ensure the safety of specific object and each person on the planet. At the same time we must not forget that professional swindlers usually know how to neutralize the system of industrial production and only unknown device may be an obstacle in their way.
There are good reasons to use the technology of FPGA for development of the navigation system, due to their flexibility and easy reconfiguration.

Topicality

Electronics in modern life is so rapidly evolving and complicated that it is impossible without the navigation system. In addition, the use of FPGA significantly increases the prospects of development and makes it more modern. Another criterion for the use of FPGA is the need to sharply reduce time and costs for design and improve the ability to modify and debug the equipment.

Aim

Development and research of the structure of the navigation system, providing higher technical and economic characteristics in comparison with analogues.

Tasks

To achieve this aim are the following tasks:

Development of the structure of the navigation system that based on the FPGA.
Development of navigation system prototype that based on FPGA.
Experimental investigation of the navigation system for technical and economic parameters.

Scientific significance

Will make a new structure for the navigation system based on FPGA, which differs from analogues on technical and economic characteristics.

The practical value

The developed system is a part of the technological complex of security device that includes a number of functions, definitions and reporting about the location of a moving object, for example - car.
The advantages of this design include low cost and relative compactness of the device, which is achieved through the use of FPGA-design technologies. It is also provides the flexibility of design. The benefits of the project are: action-oriented work, the use of modern element base and FPGA-complex to debug the project, finished prototype.

Main results and objects of researching

The main objects of study are: GPS-receiver GlobalSat EM401 based on SiRF Star II chipset and microcontroller MICROBLAZE, from debug board SPARTAN 3E Development KIT, firm XLINX.
In designing this hardware and software products were used high-level programming languages: C, C++ and integrated software package for the development of embedded programmable processor systems based on FPGA - Xilinx Embedded Development Kit (EDK).

At the moment, main result of this work - the program and data processing algorithm GPS-module of security devices, and interface circuit that matching the GPS-receiver with a microcontroller MICROBLAZE. Also we studied in detail the characteristics GPS-module, a standard GPS-Protocol NMEA, his basic commands, RS-232 interface, and interface elements datasheets. Expected results: an algorithm and program coordination GPS-module with the FPGA.
GPS-receiver GlobalSat EM401 is an integral part of the complex technological security device based on GSM/GPS/FPGA-technology, the main feature of which lies in the fact that its management is carried out by using a mobile phone. The query is formed by FPGA-microcontroller, which uses GPS-receiver and activates the determination of local object coordinates, which determines the location of a moving object. Ultimately, the data with the coordinates of the object through the FPGA-microcontroller transmitted and get back to the user's mobile phone . The structure of this information-security complex is shown in Picture 1 [1,8,9].

Picture 1 - Structural diagram of security device based on GSM/GPS/FPGA 9 frames. Delay time: after the first frame = 3 sec; after the other frames = 1 sec. Number of repetitions = 10 animations. The size of the animation: 700px х 290px. File size: 93.2 Kbytes. Created by GIF Animator

Description of the GPS-receiver GlobalSat EM401

GPS-receiver (picture 2) has a simple five-wire connection (1 - ground (GND); 2 - power (+5 V); 3 - GPS RX data input, 4 - GPS TX data output, 5 - ground (Shield, GND)). It is powered by 5 V, but can also work from the power supply 3.3 V. Data from/to the device are transmitted through a well-known RS-232 interface. EM401 can be connected via the COM-port to a personal computer [2,5].

Picture 2 - GlobalSat EM401

Cold Start - 18 minutes. This is the period when the GPS-module does not have primary data about the time and location, so it is impossible to immediately determine which of the 24 satellites are in sight. In this case, the module searches all the 24 satellites that takes some time.
Warm Start - 5-6 seconds. Module saves date, time and location information in memory. Next time it is turned on it uses that information for faster GPS fix. With built in RTC (Real time clock) used time is current, not the same as was when module last time worked [10].
The basis of GPS-receiver - chipset SiRF Star II, developed by SiRF [11]. He is able to receive the signal in urban or dense woodland, and also supports 12 channels, so - 12 satellites simultaneously. This is more than enough, because to determine the exact 2-D location (latitude and longitude) is sufficient signals from 3 satellites, in the presence of 4 satellites, it is possible to determine also the height above sea level (3-D format).
GlobalSat EM401 uses a data protocol standard - NMEA. Format of data in NMEA - EIA-422A, but for the most cases it is compatible with RS-232 at 4800 bps, 8 data bits, no parity and one stop bit (8N1). NMEA 0183 line are the ASCII character set. Every sentence begins with dollarsign ($) and ends with carriage returns linefeed ( ). Data - comma delimited. All commas must be included, since they act as markers. The checksum is added at random. After a $ sign should be address area: aaccc. aa is the id = GP, which is used to identify data GPS. The transfer device id is usually additional [6,7].

Table 1. Data Format of the NMEA-string

Beginning of string	The ID of the string address	Empty field or data field	...	Empty field or data field	Optional checksum field	End of string
"$" HEX 24	'address field'	[","+ 'data field' ]	...	[","+ 'data field' ]	["*"+ 'checksum field' ]	'CR''LF' Hex 0D 0A

Used GPS-module EM401 provides a continuous state of the four main outputs NMEA command: GGA, GSA, GSV and RMC, which contain key information about the location, time, quality of data; displayed mode of GPS-receiver; determined the number of used and visible satellites, their numbers and parameters that are used in the solution of navigational problems.
Examples of messages:

$GPGGA, 161229.487,3723.2475,N, 12158.3416,W, 1,07,1.0,9.0,M, ,M,0000*18
$GPGSA, A,3,07,02,26,27,09,04,15,,,,,,1.8,1.0,1.5*33
$GPGSV, 2,1,07,07,79,048,42,02,51,062,43,26,36,256,42,27,27,138,42*71
$GPRMC, 161229.487,A,3723.2475,N,12158.3416,W,0.13,309.62,120598,,*10 [7]

Thus, algorithm development data from the GPS-module of the protective device involves capturing data from these commands from a serial COM port, identification, processing and subsequent allocation of the necessary components. The main difficulty lies in the fact that the reception-transmission through the COM port require strict compliance with RS-232 interface. Undoubted advantage is that the NMEA-protocol is compatible with RS-232.
Summing up , the algorithm can be divided into two main phases:

Catch, reading and receiving NMEA-commands from the selected COM port.
A breakdown of NMEA-commands and the choice of necessary data.

Scheme of data processing GPS-module of the protective device shown in picture 3.

Picture 3 - Scheme of data processing GPS-module of the protective device

Construction of the interface matching circuits GPS-Receiver GlobalSat EM401 with a microcontroller MICROBLAZE

To synchronization of all modules, and program management of the software is using the microcontroller MICROBLAZE. The microcontroller software is implemented on FPGA.
The main way to exchange information between modules of security complex is the transfer through a COM port. The difficulty is that the reception-transmission through it requires strict compliance with RS-232, according to which a high signal level corresponds to a voltage 3 .. +15 V, and the lower -3 ..- 15 V. In turn, GPS module uses a low power supply - 3.3 V, while data is transferred to the low voltage levels - Low Voltage TTL, which levels of signal do not exceed + -1.5 V. Therefore, for consistency, you can use IC MAX232 or MAX3232, which harmonize stress levels to 5 V and 3.3 V, respectively [1].
In the project using the COM port is more preferable than USB. This is primarily due to the fact that the board 3E Development KIT has two COM ports for interfacing with other devices. The second advantage is that the NMEA-protocol which are used by GPS-receiver GlobalSat EM401 for data transmission is compatible with RS-232.
The basic detail of the interface matching circuits GPS-Receiver GlobalSat EM401 with a microcontroller chip MICROBLAZE is MAXIM 3232. It is commonly used the converter levels of signals to TTL-CMOS voltage range 3 .. 5.5 V. It is equipped with proprietary output stages of transmitters, which provide low voltage drop and full compatibility with the requirements of the standard RS-232 at a supply voltage from 3,0 to 5,5 V. The formation of the output signal when using a single positive voltage supply is provided with two built-in pump generator. This device contains two receivers and two transmitters [12].
Wiring diagram for GlobalSat EM401 to COM-port of the microcontroller is shown in Picture 4 [1].

Picture 4 - Wiring diagram for GPS-module to a COM-port
The second an important element of the interface matching circuits is linear voltage stabilizer LM7805 (domestic analogue - KR142EN5) [13].
After soldering all the elements in the development board has been received interface matching circuits GPS-Receiver GlobalSat EM401 with a microcontroller MICROBLAZE, shown in picture 5.

Picture 5 - The interface circuit matching GPS-Receiver GlobalSat EM401 with a microcontroller MICROBLAZE

Conclusion

During the implementation masters work was studied the problem developing the structure of the navigation system based on FPGA-technology.
Work with the hardware - a very complicated and laborious process, requiring high moral and material costs, so the process of debugging the project with using the debug board is still ongoing.

Links

1. Grudinin A.A. Pohomov A.A., Medvedev K.V., Zinchenko E.Y., Medgaus A.I. Zinchenko J.E.; report "Car alarm system based on GSM/GPS/FPGA"; Information and computer technology - 2010 // collection materials of the sixth international scientific conference of students, graduates and young scientists - Donetsk, Donetsk National Technical University - 2010.

2. User's guide for GPS-receiver GlobalSat EM-401. // web-resource
http://www.sparkfun.com/datasheets/GPS/EM-401%20User%20Manual.pdf

3. Gaymore I., "New family of GSM/GPRS/EDGE/GPS module of the company Siemens, targeted at automotive applications", Journal "Wireless technologies" № 2, 2008. // web-resource
http://www.wireless-e.ru/articles/modules/2008_2_14.php

4. Dempster A.G., Parkinson K.J., Engel F., Mumford P., Rizos С.; The UNSW/NICTA FPGA-based GPS Receiver: A Tool for GNSS Research; General Dynamics // web-resource
http://www.dynamics.co.nz/media/V1/indicon2005.pdf

5. Article in Wikipedia about RS-232 // web-resource
http://en.wikipedia.org/wiki/RS-232

6. Protocol NMEA and control command of GlobalSat GPS-receivers // web-resource
http://fort21.ru/download/protocol_nmea.pdf

7. Reference manual NMEA-commands for the SiRF-devices// web-resource
http://www.sparkfun.com/datasheets/GPS/NMEA%20Reference%20Manual-Rev2.1-Dec07.pdf

8. Semenov Y.A.; wireless (radio) channels and network // web-resource
http://web.opennet.ru/docs/RUS/inet_book/3/radio_33.html

9. Site, that devoted to patterns of vector graphics // web-resource
http://www.grafikerler.net/telefon-vektorleri-t51406.html

10. Darius; "Cheap and used Sirf II e LP GPS Module"; blog, dedicated to various projects in the electronics design software.
http://www.electronicsblog.net/cheap-and-used-sirf-ii-e-lp-gps-module-from-ebay/

11. Detailed description of the architecture chipset SiRFstarII. // web-resource
http://www.hotchips.org/archives/hc11/3_Tue/hc99.s7.3.Turetzky.pdf

12. MAX3232 Datasheet // web-resource
http://datasheets.maxim-ic.com/en/ds/MAX3222-MAX3241.pdf

13. LM7805 Datasheet // web-resource
http://www.avrlab.com/node/29

14. Description of program GPSDiag that monitor incoming NMEA GPS-messages from the serial port; the official site of the developer // web-resource
http://commlinx.com.au/

15. Description of , schematic diagrams, documentation, security systems, GSM-on GSM-network (for stationary and mobile offering). // web-resource
http://www.wrjob.org.ru/guard.html#

Important note

This master's work has not completed yet. Final Completion: November 2011. Full text of the work and materials on the subject can be obtained from the author or his supervisor after the specified date.