Techniques to detect for DTX frames in a "primary" transmission that may
be sent in a non-continuous manner using a "secondary" transmission that
is sent during periods of no transmission for the primary transmission.
The primary and secondary transmissions may be the ones sent on the
F-DCCH and Forward Power Control Subchannel, respectively, in an IS-2000
system. In one method, a determination is first made whether or not a
frame received for the primary transmission in a particular frame
interval is a good frame (e.g., based on CRC). If the received frame is
not a good frame, then a determination is next made whether the received
frame is a DTX frame or an erased frame based on a number of metrics
determined for the primary and secondary transmissions. The metrics may
include symbol error rate of the received frame, secondary transmission
(e.g., PC bit) energy, and received frame energy.