Data from London’s commuters reveals travel patterns in unprecedented detail. It also raises privacy fears. Read more: http://ow.ly/1bD7x
DTMF decoding by GSM modem
DTMF decoding by GSM modem http://ow.ly/1gZU6
GSM Audio Codec & DTMF. Why the Half Rate Codec could force trouble?
The DTMF signal is generated by a separated source, typically a landline (corded) phone, and sent to the input lines of the module (Uplink path). The frequencies couples, sent on the voice channel , are digitised, encoded and sent by the digital transmission system. In the receiving device the signal would be reconstructed, but since […]
Broadband Wireless Local and Remote Sensing
Sensor networks are also increasingly being used for monitoring and controlling vital operations in industries, hospitals, and military installations and vehicles. Current research trends concentrate on Radio Frequency (RF) technology for sensor communications. However, OW communications or Visible Light Communications (VLC) can offer a much higher data rate or higher reuse factor. Comparison speed versus […]
Stamp sized GPRS module (mm) 22x22x3
Have you ever seen a smaller GSM module? Ultra small size (22x22x3 mm), lightweight (3.2 g) and easy to integrate Low power consumption R&TTE type approval plus CE, GCF, FCC, PTCRB, IC Full RS232 on CMOS level with flow control (RX, TX, CTS, RTS, CTS, DTR, DSR, DCD, RI) Embedded TCP/IP Stack UDP/IP Stack , […]
A 50-Watt Cellular Network. Solar-powered base stations can link up remote rural areas
A 50-Watt Cellular Network. Solar-powered base stations can link up remote rural areas http://ow.ly/1bCKj
DTMF encoding by GSM modem
It is not easy to detect and recognize DTMF with satisfactory precision. Often, dedicated integrated circuits are used. It is rather complicated, so it is used only marginally. Most often, a MT8870 or compatible circuit would be used. The MT8870 is a complete DTMF receiver integrating both the band split filter and digital decoder functions. […]
GSM module located by Timing advance
GSM module located by Timing advance TA. Example on TA combined with Angle of Arrival and analysing sector antennas http://ow.ly/14y7U 13.03.2010 Remark of the author after sending the tweet: I am working on a GSM based locating system that will cover 180 countries. The first GSM based locating I launched 10 years ago at World […]
SIM card on Chip VQFN8 SIM UICC form factor specified as ETSI TS 102 671
Tim Evans (Vice Chair ETSI SCP at ETSI) mentioned at message board at Linkedin (13.03.2010): “I am pleased to inform you that ETSI SCP agreed the new VQFN8 SIM UICC form factor last week as ETSI TS 102 671.” Remark of the author of the blog: VQFN8 SIM cards are an interesting technology to create […]
Indoor locating on WIFI 802.1b
Indoor locating on WIFI 802.11b. Accuracy: One meter or even less http://ow.ly/1gZJX