User's Manual

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MEMO
FUNCTION
SVM 2G4HZ Frequency hopping
The number of used frequencies (NUF) in the hopping algorithm is 95.
In base and handset a Primary Hopping lndex Number (PHIN) exist.
This number is incremented modulo NUF in the end of the normal
downlink half-frame. It is broadcast in Q0 message instead of PSCN.
To a simplex or established duplex bearer a Hopping Index Offset
(HIO) is assigned, which is an analogue to the used RF carrier in a
FDMA system. This value is broadcast in place of CN in Q0
message. In the base in all unable slots in up-link direction the
receiver is scanning with HIO=0. the receiver is scanning with doesn’t
exclude RF-carriers.
Different base use different hopping sequences. The different
sequences are derived from the hopping table by adding an offset,
SeQuenceCode (SQC).
A hopping table maps an index I to a carrier number: CN = f(I)
The physical RF carrier is calculated by the formula:
CN = (f ((PHIN+HIO) mod NUF) +SQC )mod NUF for 10.368000
MHz crystal frequencies are derived as: Frequency : 2401.056 MHz +
CN*0.864000 MHz
Fast Frequency Hopping : (DCT 2G4) , up to 800 hops/sec
This wireless microphone is connected with DVR and record by audio
receiving.