8.4 MHz (4.2 MHz for downlink and 4.2 MHz for uplink). How many bandwidth (4.2+4.2 voice channels can be offered in each cell if the frequency up & down) reuse factor is 3? Re-use factor Answer Single carrier 200 kHz bandwidth The maximum number of users which can be simultaneously Voice channels connected to a GSM system in each cell is calculated to be 56. per carrier The frequency utilisation efficiency is equal to 13.33 voice channels per megahertz of bandwidth per cell. GSM resource allocation is illustrated in Figure 10.17. Broadband Telecommunications Technologies and Management Carrier frequency f is reused Carrier frequencies Figure 10.18 Frequency reuse in 2G systems Table 10.3 2G standards Standard Countries/region Pan-Euopean and then worldwide D-AMPS North and South America, Australia Japan Japan Worldwide GSM was by far the most successful among the TDMA-based 2G technologies, and was rolled out in 212 countries and territories as reported by GSM World Statistics [6]. In comparison the D-AMPS standard was not SO successful and was primarily rolled out in North and South America. Most D-AMPS operators completely migrated to GSM and its 3G evolu- tion in the late 2000s. In addition to GSM and D-AMPS two TDMA standards were developed and commer- cialised in Japan: Personal Digital Cellular (PDC) and Personal Handy-phone System (PHS). These remained mostly confined to the Japanese market and have also been mostly phased out. Table 10.3 lists the 2G TDMA technologies. Terrestrial Broadband Wireless Telecommunications Code Division Multiple Access Another digital voice, and later data, mobile communications system is considered to be a 2G standard. It was developed and standardised in the United States under the auspices of the TIA. It is called Interim standard 95 (IS-95) and used a novel technology known as Code Division Multiple Access (CDMA) and was developed by Qualcomm, Inc., a US company. IS-95 (or cdmaOne) became a successful global system and a direct competitor to other 2G standards such as GSM,