I am designning a 868MHz RF modules, but i am not familiar with the regulation of this band (868 - 868.6MHz). If ASK and FSK use as the modulation technique, so what is the max. allowed data rate of them, respectively? Hope someone can teach me,,,thank you.
Re: What is the max. allowed data rate at the 868.35MHz band
Hi,
There are theoretically/in general no limit for the data rate at this ISM band. However, the duty cycle, transmit power, etc. regulations and modulation bandwidth, BER requirements of your application put certain limits on the maximum data rate in practice. You are in principle free to trade these parameters.
Example: IEEE 802.15.4 / Zigbee at 868 MHz
The data rate is 20kbits/s, but the chip rate is 300 kchips/s.
Re: What is the max. allowed data rate at the 868.35MHz band
ZigBee data rates:
868MHz
20 kbps (1 bit/symbol, 20 kBaud)
Data modulation is BPSK with differential encoding
Spreading code is a 15-chip m-sequence
Chip modulation is BPSK at 0.3 Mchips/s
Low rate for better sensitivity and larger coverage area
2.4 GHz
250 kbps (4 bits/symbol, 62.5 kBaud)
Data modulation is 16-ary orthogonal modulation
16 symbols are ~orthogonal set of 32-chip PN codes
Chip modulation is MSK at 2.0 Mchips/s
High data rate to attain high throughput