ANT Forum

Do you have any app notes describing how the search process takes place? How much radio on time is required for the sender/receiver (or master/slave)? Are multiple frequencies used?

The protocol document goes in depth on the protocol between the host and the radio, but how many bytes are being transmitted between the sending and receiving radios for the minimally sized message?

Thanks,
Shawn      

There is a recently released app note on channel search on the DevZone. Channel search only takes place in a single frequency at a time (the frequency configured in the channel you are searching for). If a receiver opens multiple channels at the same time, search will take place in parallel if they are on the same frequency, and sequentially, if on different frequencies.

The payload for transmission over the air is 8 bytes per packet (fixed).      

"Ant Channel Search," ANT AN11, rev. 1.0

Table 6-1: Worst Case Channel Acquisition

...lists acquisition times that are much longer than the message period. It's unclear what the search timeout configuration is for this example. I guess it would have to be a low priority search?

Is there any reason why a high priority search would fail to establish a connection within the messaging period, assuming zero packet loss? (e.g. with a 0.5Hz Message rate, the worst case search time would be 2 seconds).

I'm confused about the statement, "There is no mathematical formula for calculating these numbers."

Thanks,
Shawn      

The receiver is not active the entire time while searching for a channel, that is why the worst case search time is longer than the message period.