GoHigh MG3000-R, User Manual

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Caller ID: switch sends the caller information to callee, such as number, name, date and
time etc..
Basic method: Switch of originating end send caller information to the switch of
destination through inter-office command system , and the switch of destination will send the
information to end user in FSK (Frequency-Shift Keying) or DTMF (Dual Tone
Multi-Frequency).
FSK has two sending ways: CID sending of on hook (Type 1), CID sending of off hook
(Type 2). For type 1, it can be divided into: sending before the first ring, send between the
first ring and the second ring.
FSK CID modulation standard has two types: Bell202 and ITU-T V.23. ITU-T V.23 use
frequency 1300±10Hz as 1, and frequency 2100±10Hz as 0; Bell202 use 1200±10Hz as 1,
and 2200±10Hz as 0. The bit rates of both are 1200bps.
FSK CID data has 2 types: SDMF (Single Data Message Format), MDMF (Multiple Data
Message Format). For SDMF, the format structure is simple, and only a little information can
be included (Caller ID, Date and Time); while for MDMF, the format structure is more
complex, and it can include more information, besides what is included in SDMF, it can also
include Caller ID name etc..
Currently, in these countries, such as USA, China, Japan, UK, Canada, Belgium, Spain,
Singapore etc., FSK is adopted. However, the standards vary in different countries: North
America and China adopt Bellcore standard; most of European countries adopt ETSI
standard; Japan adopt NTT standard; UK adopt BT standard. Countries which adopt DTMF
are India and Sweden etc..
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FSK (Frequency-shift keying) use digital signal to modulate the carrier frequency, which
is applied very early and widely in data transmission because of its main advantages
including: realizing easily, good performance in anti-noise and anti-attenuation.
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DTMF (Dual Tone Multi-Frequency) converts the key events into the corresponding