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1 tracker composition
1, GPS signal receiving portion
Frequently receiver chip
(1) SiRF starⅡ e:. [ 123]
SiRFstarⅡe is the first piece of high-performance GPS chip, released in 2002. SiRFstarⅡe / LP (GSW2.3) is SiRFstarⅡe low-power version. Both use 1920 Ci / frequency correlator, cold boot / warm boot / Hot start time respectively 45s / 35s / 8s, a satellite 12 may simultaneously track. It should be said, this 2-chip index has to meet the needs of everyday applications, launched in 2003 and 2004 non-independent GPS products extensive use of these two kinds of chips. .
used GPS receiver chip
(2) SiRF starⅢ:
SiRF chip has released the latest third-generation chip SiRFstarⅢ (GSW 3.0 / 3.1) in 2004, so that civilian GPS chip boarded a peak in terms of performance, greatly enhance sensitivity than the previous product. By using this chip 200,000 / frequency correlator (Correlators) increase sensitivity, cold boot / warm boot / Hot start time respectively 42s / 38s / 8s, can simultaneously track 20 satellite channels. Many Launched in 2005, the latest non-independent GPS receivers used this chip. .
(3) Sony single chip solution CXD2951:
SONY third generation chip, they are only RF packet together with baseband, Sensitivity: -152dBm.
2, GSM / CDMA emission portion
GSM module GSM RF chip, baseband chip, memory, amplifiers and other devices in an integrated circuit board, which has an independent operating system, GSM RF processing, baseband processing module and provides a standard interface function.
ARM developers or GSM module to control the microcontroller to implement various wireless communication function, for example, by GSM module in communication with the RS232 serial port, using a standard AT command: send SMS messages, phone calls, GPRS dial-up networking. Based on the development of GSM module products are often based on the ARM platform, using embedded systems development. Some GSM module has ldquo; open platform built rdquo; feature that allows customers to embed their software platform to program within the module.
GSM module first major manufacturers in foreign countries, including Siemens, Wavcom, Sagem, etc.; with the domestic technical progress, such as domestic manufacturers Huawei, Simcom, BenQ modules due to a higher price, it has been gradually replaced foreign brands in the domestic market accounted for the mainstream position. On the market more popular module comprises Huawei GTM900-B, Siemens Mc39i, Wavecom’s Q24 etc.
3, receiving platform portion
Network Operator (Unicom or mobile) you open a service port (approximately 6000-10000), and then build your own website. Systems generally use B / S (browser / server) structure, without building any system, there is no need to install any software, as long as the computer with Internet access can achieve fast and accurate dispatch enterprise management.
the following query: system interface into the site, select the query above GoogleEarth interface, the system starts the real-time query number and the query results are displayed in the page, the user clicks on GoogleEarth view, it can pass GoogleEarth satellite map provided see the actual position of the vehicle. If you want to, if desired, the positioning of the following conditions:
(1) GPS receiver device 600 generallyThere are many brands ranging from 2000 (responsible for receiving satellite signals);
(2) network platform (the position of the people you want to observe or things);
(3) of the network operator support (information network platform via the network operator’s base station and to convey the reaction);