Wireless Oom

Compressed mode allows a UE to perform interfrequency measurements.

One importance between CDMA and TDMA is that

In CDMA, the UE transmits and receives continously during all the frames and slots.

In TDMA the UE is only active during one slot in a frame.

Then, during the rest of the slots, the receiver can be tuned to other frequencies and perform measurements.

With CDMA, this is not possible to make interfrequency measurements unless the receiver structure is duplicated.