Amplitude-Shift Keying

Attribute	Value
UHF Band Name	LPD433, SRD860 (ISM)
Carrier Freq.	433 MHz, 868 MHz
Bandwidth LPD	1.7 MHz (433.05 – 434.79)
Data Rate	4 KHz, maybe more?

General Notes

• Generic 433 MHz RX/TX chips with ASK.
• Transmitter is on if data pin is high. Receivers have automatic gain control. Will output random noise when there is no signal. Requires an error checking protocol.
• Use manchester encoding and training preamble for receiver and transmitter to sync up their clock phases.
• Encrypted serial connection over 433 MHz?

Planned Modules

• Frequency-shift keying (FSK)
• Phase-shift keying (PSK)
• Chirp spread spectrum (CSS)

Further Links

• Line code
• Clock recovery
• Manchester code
• Error correction code
• Noisy-channel coding theorem
• Nyquist–Shannon sampling theorem
• Short range device frequencies