OpoRek.Com

UNMJ4ZZZS4U3

In general, a GSM/GPRS modem is recommended for use with a computer to send and receive messages. This is because some mobile phones have certain limitations comparing to GSM/GPRS modems.

Some of the limitations are described below:

• Some mobile phone models (example: Ericsson R380) cannot be used with a computer to receive concatenated SMS messages.What is a concatenated SMS message?
  A concatenated SMS message is a message that contains more than 140 bytes. (A normal SMS message can only contain at most 140 bytes.) Concatenated SMS works like this: the sender’s mobile device breaks a message longer than 140 bytes into smaller parts. Each of these parts are then fitted in a single SMS message and sent to the recipient. When these SMS messages reach the destination, the recipient’s mobile device will combine them back to one message.

  What is the cause of the problem?
  When the mobile phone receives the SMS messages that are parts of a concatenated SMS message, it combines them to one message automatically. The correct behavior should be: when the mobile phone receives the SMS messages that are parts of a concatenated SMS message, it forwards them to the computer without combining them.

• Many mobile phone models cannot be used with a computer to receive MMS messages. Because when they receive a MMS notification, they handle it automatically instead of forwarding it to the computer.
• A mobile phone may not support some AT commands, command parameters and parameter values. For example, some mobile phones do not support the sending and receiving of SMS messages in text mode. So, the AT command “AT+CMGF=1″ (it instructs the mobile phone to use text mode) will cause an error message to be returned. Usually GSM/GPRS modems support a more complete set of AT commands than mobile phones.
• Most SMS messaging applications have to be available 24 hours a day. (For example, an SMS messaging application that provides ringtone downloading service should be running all the time so that a user can download ringtones any time he/she wants.) If such SMS messaging applications use mobile phones to send and receive SMS messages, the mobile phones have to be switched on all the time. However, some mobile phone models cannot operate with the battery removed even when an AC adaptor is connected, which means the battery will be charged 24 hours a day.

Besides the above issues, mobile phones and GSM/GPRS modems are more or less the same for sending and receiving SMS messages from a computer. Actually, you can consider an AT-command-enabled mobile phone as “GSM/GPRS modem + keypad + display + …”.

There is not much difference between mobile phones and GSM/GPRS modems in terms of SMS transmission rate, since the determining factor for the SMS transmission rate is the wireless network.

Related posts:

1. What is a GPRS Modem? A GPRS modem is a GSM modem that additionally supports the GPRS technology for data transmission. GPRS stands for General Packet Radio Service. It is a packet-switched technology that is an extension of GSM. (GSM is a circuit-switched technology.) A key advantage of GPRS over GSM is that GPRS has a higher data transmission speed. GPRS [...]...
2. Introduction to AT Commands AT commands are instructions used to control a modem. AT is the abbreviation of ATtention. Every command line starts with “AT” or “at”. That’s why modem commands are called AT commands. Many of the commands that are used to control wired dial-up modems, such as ATD (Dial), ATA (Answer), ATH (Hook control) and ATO (Return [...]...
3. What is an SMS Gateway? One problem of SMS messaging is that SMSCs developed by different companies use their own communication protocol and most of these protocols are proprietary. For example, Nokia has an SMSC protocol called CIMD whereas another SMSC vendor, CMG, has an SMSC protocol called EMI. We cannot connect two SMSCs if they do not support a [...]...
4. Introduction to GSM/GPRS Modems A GSM modem is a wireless modem that works with a GSM wireless network. A wireless modem behaves like a dial-up modem. The main difference between them is that a dial-up modem sends and receives data through a fixed telephone line while a wireless modem sends and receives data through radio waves. A GSM modem can [...]...
5. AT Command Operations There are four types of AT command operations: Test operation. A test operation is used to check whether a certain AT command is supported by the GSM/GPRS modem or mobile phone. Set operation. A set operation is used to change the settings used by the GSM/GPRS modem or mobile phone for certain tasks. Read operation. A read operation [...]...
6. SIM300C/340C GSM/GPRS Modem Product Name: SIM300C/340C The SIM300C/340C is a complete Tri-Band/Quad-Band GSM/GPRS solution in a compact plug-in module with DIP board-to-board connector, which can be used in M2M applications such as telemetry, telematics and other M2M mobile data communication systems. • DIP type board-to-board connector suit for vehicle application • Customized MMI and keypad/LCD support • An embedded Powerful TCP/IP [...]...
7. SIM508/548 GSM/GPRS/GPS Modem SIM508/548 module is a Tri-Band/Quad-Band GSM/GPRS-enabled module that is also equipped with AGPS technology. The compact design of the SIM508/548 makes it easy to integrate GSM/GPRS & GPS as an all-in-one solution. You will save significantly both time and cost for the integration of additional hardware components. The combination of both technologies can fit almost [...]...
8. Implementasi Metode Kontrol v,omega pada Mobile Robot Title: Implementasi Metode Kontrol ν,ω Berbasis Proporsional Integral Untuk Kontrol Gerak Mobile Robot Berpenggerak Differensial : Studi Simulasi Abstrak : Pengembangan teknik otomasi pergerakan robot untuk dapat beroperasi di dunia nyata sudah menjadi bahan penelitian bagi pengembangan mobile robot di dunia saat ini. Untuk dapat mencapai suatu posisi yang diinginkan dari posisi awal, mobile robot membutuhkan [...]...