Panasonic KX-TG2220BXB, Service Manual, Page: 43 / 86

13 DESCRIPTION
13.1. Frequency
The frequency range of 2426.10875 MHz ~ 2448.63775 MHz is used. Transmitting and receiving channel between base unit and
handset is same frequency. Refer to the Frequency Table.
13.2. Time Division Duplex (TDD) operation
Transmission/reception between the base unit and handset is performed by time-sharing as shown in Fig. 7. 1 slot time of
transmission and reception is 1mS. Same frequency is used in transmitting and receiving. The figure shows an example; the
frequency of 3ch is used in transmitting between the base unit and handset.
Fig. 7
13.2.1. TDD Frame Format
The TDD frame is 2mS in length. Each subframe contains 128 bits of 7.8µS duration.
Each subframe consists of the following four fields:
• • • •
A 1-bit Preamble field
•
• •
•
An 8-bit Data Channel field
• • • •
An 16-bit Sync Word
• • • •
A 72-bit ADPCM Payload (Parity 8-bit)
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KX-TG2220BXB / KX-TG2220B XF / KX-TG2220B XS / KX-TGA226BXB / KX-TGA226BXF / KX-TGA226BXS