A transmitter (22) of a telecommunications system transmits hopped pilot
signals as a distinct (i.e., locally unique) time-frequency shift of a
time frequency plane array wherein the pilot signals are hopped using a
hopping sequence. Differing transmitters of the system (20) preferably
transmit using different time-frequency shifts of the same time frequency
plane array. The transmitter (22) knows which hopping sequence to employ
to generate the time frequency plane array in view of its storage of the
hopping sequence, and further knows how to perform its signature
time-frequency shift the time frequency plane array thusly created in
view of its storage of the time-frequency shift pattern. A receiver (24)
identifies a transmitter from which the receiver obtains signals by
detecting the particular time-frequency shift of the time frequency plane
array and associating the particular time-frequency shift with the
originating transmitter. Upon detecting the time frequency plane array of
its received signals, the receiver (24), which knows the hopping sequence
employed to generate the time frequency plane array, can determine how
the time frequency plane array has been time-frequency shifted, and upon
determining the pattern of the shift can associate the received signals
with one of the transmitters for which the receiver (24) has stored
time-frequency shift patterns in its library (86).