Overview
GSM module has all the basic functions of sending SMS SMS, voice call, GPRS data transmission, etc. Based on GSM networks. For a simple purpose, the GSM module plus keyboard, display and battery, is a mobile phone.
Developers use ARM or microcontrollers to communicate with GSM modules through RS232 serial ports, using standard AT commands to control various wireless communication functions, such as send SMS, call, GPRS dial-up, etc. The development of GSM module products is often based on ARM platforms, using embedded systems. Some GSM modules have the "Open Built-in Platform" function that allows customers to embed their own programs into the software platform within the module.
Early GSM modules are mainly for mobile vendors, mobile factory directly purchase modules, and equipped with external devices can produce a mobile phone. The GSM module solves complex RF transmission and baseband processing issues in mobile phone design, and provides standard communication interfaces. The manufacturer does not have to start the design of the phone from the underlying chip level, shorten the design cycle. 5 years ago, the domestic mobile phone manufacturers almost all the products of the finished product GSM modules were used for secondary development and production of mobile phones. In recent years, with the gradual maturity of domestic mobile phone design companies, mobile phone manufacturers get rid of the dependence on GSM modules, turn In order to start the mobile phone directly from the chip level.
Due to factors such as working hours, environmental requirements, the GSM module is still in a wide range of industrial applications, and products that can be applied to GSM modules can be seen in all walks of life. For example, in the field of in-vehicle monitoring, the GSM module is used to transfer the vehicle's GPS data back to the vehicle management center; in the electric power, water system, the remote smart meter reading can be monitored by the GSM module, and the user's electricity and water can be monitored in real time; The surveying and mapping industry has installed a real-time monitoring for a lot of remote surveying points. It does not have to be manually collected; in the family, the wireless alarm system can be installed. Once the fire or theft, you can immediately notify the head of the household and alarm; Foreign countries, many of the elderly children bring personal trackers to prevent elderly and children from being lost or unexpected, and it is also integrated GSM module. It can be said that with the improvement of the network construction of GSM, the application range of the GSM module is getting wider.
Description
The GSM module can be divided into a GPRS module, an EDGE module, a 3G module, and a pure SMS module according to the supplied data transfer rate. SMS modules only support SMS services. GPRS can be said to be the continuation of GSM. It is often described as "2.5g", which means that this technology is located between the second generation (2G) and the third generation (3G) mobile communication technology. The transmission rate of GPRS is from 56K to 114kbps, the theoretical speed is up to 171K, and the actual test speed is about 25k. With respect to GSM's 9.6kbps access speed, GPRS has faster access to data communication speed, and GPRS technology also has at any time, any location, can be connected, always online, with traffic billing. The EDGE technology further enhanced the rate of data transmission to 270K, known as "2.75g", and the data transfer rate is 2 times in GPRS. Domestic GSM network generally has GPRS communication features, mobile and Unicom networks support GPRS, and EDGE has also covered nationwide.
GPRS module is a GSM module with a GPRS data transfer function. The GPRS module is a streamlined mobile phone. The main functions of integrated GSM communications are on a board, with feature that transmits short messages, calls, data transmission. The GPRS module is equivalent to the core part of the phone. If the keyboard and the screen are a complete mobile phone. Ordinary computers or microcontrollers can be connected to the GPRS module via the RS232 serial port, and control the GPRS module through the AT instruction to implement various GSM-based communication functions. The
GPRS module distinguishes the traditional pure SMS module, both of which are GSM modules, but the SMS module can only send texting and voice communication, and the GPRS module also has a GPRS data transfer function.
GSM module manufacturers are the earliest mainly in foreign countries, including Siemens, WAVCOM, SAGEM, etc .; With domestic technical advances, domestic manufacturers such as Huawei, QuECTEL, SIMCOM, BENQ and other modules Higher cost performance has gradually replaced the mainstream of foreign brands in the domestic market. The popular module in the market includes Huawei GTM900-B, Siemens' DTP _rd + , Wavecom's Q24, etc., domestic utilization module successfully develops terminal MODEM products typical application Javai JWOD1, Jing Wei Xinghang JWOD2.
Application
Siemens, Wavecom, Huawei, Shiyuan Communication (QUECTEL), SIMCOM, BENQ and other modules in China, more typical applications Jingxis Navigation JWOD1, Jingxing Star Air JWOD2, News Top MD231. Successful cases are:
dtp_t05 series embedded SMS module GSM MODEM
dtp_rd + series integrated SMS alarm smart terminal IDTU
Mobile base station optical fiber communication equipment remote real-time monitoring
eight-channel input output series SMS wireless control terminal