Developement of Remote Appliance Control through SMS and DAQ

Same other ways gsm is used get the status of the sales happened on the counter without the intervention of the operator. Pic microcontroller and gsm modem will work togetther to form the system where at a particular stage it will sends the sms to the senior sales officer about the sales of particular time periods.
GPRS Telephones
-Due to the fact that more than one channel is used for downlink, the GPRS mobile phones make possible greater data transmission speeds. There are several types of phones with regard to the number of channels they use for data transmission...
• Type 2+1 – two downlink channels and one uplink data transmission channel
• Type 3+1 – three downlink channels and one uplink data transmission channel
• Type 4+1 – four downlink channels and one uplink data transmission channel
-The GPRS mobile phones can be classified into the following three classes in terms of the possibility of simultaneous calls (via GSM) and data transmission (via GPRS).
• Class A – Simultaneous calls (via GSM) and data transmission (via GPRS)
• Class B – Automatic switching between the GSM and the GPRS mode is possible according to telephone settings.
• Class C – Hand operated switching between the GSM and the GPRS mode
GPRS could possibly be the technology that will allow consumers to really begin to pursue the mobile Internet. GPRS is considered one step ahead of HSCSD (High Speed Circuit Switched Data) and a step towards 3G (Third-generation) networks. It is the step to 2.5G for GSM and TDMA (Time Division Multiple Access) service providers.

GPRS is ideal for Wireless Application Protocol (WAP) services because of the cost saving WAP over GPRS bring to mobile operators and cellular consumers. Costs are reduced because GPRS radio resources are only needed while the message is being transferred. For the end user, that means you only pay for the time it takes to download the data and information that you need. For the GSM operator, that means that you will be able to provide high speed Internet access to consumers at a reasonable cost, because you will bill mobile phone users for only the amount of data that they transfer rather than billing them for the length of them that they are connected to the network.