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Chapter 6: Radio-Controlled Systems and Telemetr y 137

Figure 6.6 Hedy Lamarr, creator of the first spread spectrum patent.

Binding or Pairing
Binding for DSSS refers to the process in which the transmitter GUID and the fail-safe data
are loaded into receiver firmware. The GUID is a parameter that uniquely identifies the
transmitter to the receiver, and it is a prerequisite that the binding process be performed
before any R/C operations take place.
Futaba is another major manufacturer of 2.4-GHz R/C systems that use FHSS as their
modulation scheme. They term their FHSS technology as FASST, which stands for Futaba
Advanced spread spectrum Technology. Their binding or pairing process consists of transferring
the GUID and frequency hopping pattern from the transmitter to the receiver. Most readers
are aware of the pairing operation that is normally required prior to using a non-R/C BT
device. This BT pairing operation usually requires that the receiving device be put into a
scan mode to identify any nearby BT transmitters. The users then enter a predefined code
once the transmitter is identified and selected. The BT receiver will then load the transmitter’s
GUID and hopping pattern into the receiver’s EEPROM so that it will no longer need to be
paired the next time it is used with that particular transmitter. The actual Futaba binding
process is very simple:

• Turn on the transmitter. Check the LED on the back of the transmitter to make sure
that it is green. If so, proceed to the next step. If not, power down the transmitter and
turn it on once again.
• Turn on the receiver.
• With the receiver on, press and hold the ID Set button (located between the two
antenna exits) for more than one second. When the linking process has completed
the receiver’s LED will change to a solid green.