Cordless Section (Base Unit) - Panasonic KX-FC971CX-S Service Manual

8.12. CORDLESS SECTION (BASE UNIT)

8.12.1. Description
8.12.1.1. Frequency
The frequency range of 2400MHz~2483.5MHz is used. Transmitting and receiving channel between base unit and handset is same
frequency. Refer to FREQUENCY TABLE (P.122).
8.12.1.2. FHSS (Frequency Hopping Spread Spectrum)
This telephone is using an IC chip which has similar specification to WDCT (World Digital Cordless Telephone) and is the
cordless telephone system that can use multiple portable unit simultaneously.
The explanation of this system is mentioned below.
This system uses a Time Division Multiple Access/Time Division Duplex (TDMA/TDD) scheme:
transmitting and receiving frequencies of the base unit and cordless handset are shared in the same
frequency. The construction of RX/TX frequency data is shown below. It consists
of 6 slots from the base unit to the cordless handset, and 6 slots from the cordless handset to the
base unit, total 12 slots in 10ms. By this slot system, simultaneous air link and communication between 2 cordless handsets and
the base unit can be realized. The spread spectrum modulation techniques in this telephone is FHSS method.
FHSS makes spectrum spread by changing channel every 10ms according to
Hopping table. Also the purpose to make spectrum spread is to reduce power density per time and
per band.
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KX-FC971CX-S / KX-FGA521CX-S