Rohm LAPIS Semiconductor ML7404 Series, Hardware Design Manual

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ML7404 Family LSIs
Hardware Design Manual
FEXL7404DG-03
13
8. Standard
8.1. ARIB STD-T108
In IEEE802.15.4k, in order to correspond to ARIB STD-T108, ML7404 should be used on condition of the
following.
•
TX power: 10dBm
•
Unit channel:
5 bundled unit channel
*[2]
•
Frequency range: 921MHz~924.6MHz
*[3]
However, it is possible to deal with ARIB STD-T108 by changing a data rate to reduce the unit channel to be used.
ML7404 passed the electric wave attestation examination (TELEC-T245) corresponding to ARIB STD-T108 under the
following conditions.
Unit channel Modulation Data(chip) Rate Standard TX Power(Peak Power)
1 2GFSK 50kbps IEEE802.15.4g 13dBm
2 bundled 2GFSK 100kbps IEEE802.15.4g 13dBm
1 BPSK 100bps Sigfox 10dBm
2 bundled BPSK 40kcps Original 10dBm
2 bundled BPSK 50kcps Original 10dBm
5 bundled BPSK 200kcps IEEE802.15.4k 10dBm
*[2] a unit channel is 200kHz.
*[3] In case of using IEEE802.15.4k, in order to satisfy the spurious emission, ML7404 should be used 5 bundled unit
channel (Figure. 8.1). Therefore, it is necessary to perform CCA(Clear Channel Assessment) by 5 bundled unit
channel. But, actual transmitting occupied bandwidth (OBW) is 2 bundled unit channel (400kHz) or less. As a
result, channel separation can be made into 2 bundled unit channel (400kHz) (Figure 8.2).
Figure 8.1 Relationship between spurious emission and unit channel
Figure 8.2 Example of channel arrangement and CCA execution(3 times time sharing)
Input frequency of CW when CCA test. Bandwidth for CCA (400kHz)
-800kHz -600kHz -400kHz -200kHz fc 200kHz 400kHz 600kHz 800kHz
IEEE802.15.4k OBW
(400kHz or less)
Bandwidth of 5 bundled
unit channel (1MHz)
Adjacent Channel
Spurious emission
(<-36dBm/100kHz)
Adjacent Channel
Spurious emission
(<-36dBm/100kHz)
-400kHz -200kHz fc 200kHz 400kHz
2 bundled
Unit channel
Lower side adjacent channel
(2 bundled Unit channel)
Upper side adjacent channel
(2 bundled Unit channel)
Input frequency of CW when CCA test.