回答得很好！

The 3G-1X Mobile Assisted Interfrequency Handoff (Hard and Semisoft)
feature enables a mobile station, with a radio configuration of 3 or
higher, to report pilot measurement strengths on different candidate
handoff frequencies. Based on these results and defined thresholds, the
base station processes an inter-frequency semi-soft/hard handoff.
How the feature operates
When a base station attempts an inter-frequency handoff and the 3G-
1X Mobile Assisted Interfrequency Handoff feature is not active, the
base station uses the directed handoff neighbor and frequency lists to
determine the handoff-capable neighbors. The base station uses a
defined set of algorithms to calculate the best candidates for the
handoff. The base station then attempts to complete the semi-soft or
hard handoff to the best candidate.
When the 3G-1X Mobile Assisted Interfrequency Handoff feature is
active, the base station sends a Candidate Frequency Search (CFS)
Request message to the mobile station if all of the legs of the call are on
releases equal to 22.0 or later and if the following set of requirements
are met:
• If the call has a service option other than 33, MAIFHO is enabled.
• If the call is a 3G packet data call with Service Option 33,
MAIFHO for 3G Packet Data Call is enabled.
• The Radio Configuration for the call is greater than or equal to 3.
• The strongest pilot of the border sectors minus the strongest pilot
of the interior sectors is greater than the BPINP_COMP Threshold
as defined on the ceqface form.
• The EC/I0 Loss Metric is greater than the MAIFHO Loss Metric
threshold.

有可能終端不支持。掉話難給出比例，達到掉話的要求就會掉話，不是基本都掉。