5
2.2 Radio Frequency Power Levels:
Between the GSM1800 and the E-GSM System are differences regarding the power level. GSM1800 basically
needs lower power levels. If the performance of a MS for GSM900 system was certified of 2W (Power Class 4),
then in the GSM1800 system it is only 1W (Power Class 1). There are also reduced BTS power levels due to
microcell applications, which means instead of the 40W (Power Class 4) in the E-GSM900 system GSM1800
needs only 20W (Power Class 1).
2.3 Speech Codec
The CMD-Z7 supports the following speech codecs.
•
Full Rate (FR) Codec
•
Half Rate (HR) Codec
•
Enhanced Full Rate (EFR) Codec
The speech codec forms the human voice into a digital signal, which is sent in the GSM network.
The GSM system currently has three different speech codec standards.
At first, the Full Rate (FR) Codec was introduced. With new requirements concerning speech quality and
availability of radio channel resources two further standards were introduced, the Half Rate (HR) Codec and the
Enhanced Full Rate (EFR) Codec. The Half Rate (HR) Codec requires only half the channel capacity of a Full Rate
(FR) Channel. The Enhanced Full Rate (EFR) Codec requires the same radio channel resources as a Full Rate
(FR) Codec but offers Fixed Line quality with superior vocal clarity.
2.4 Languages
The CMD-Z7 supports the following languages:
•
Bulgarian
•
French
•
Portugese
•
Croatian
•
German
•
Romanian
•
Czech
•
Greek
•
Russian
•
Danish
•
Hungarian
•
Slovakian
•
Dutch
•
Italian
•
Slovenian
•
English
•
Norwegian
•
Spanish
•
Finnish
•
Polish
•
Swedish
•
Turkish
Preferences
GSM 900
E-GSM
GSM 1800
Frequency band
uplink:
downlink:
MHz
890 - 915
935 - 960
MHz
880 - 915
925 - 960
MHz
1710 -1785
1805 - 1880
Radio Channels
124
174
374
max. BS-Power
40 W (46 dBm)
20W (43 dBm)
max. MS-Power
2 W (33 dBm)
1W (30 dBm)
