time hopping spread spectrum (THSS)
Time Hopping(TH) means time jump. The corresponding modulation method is called Time Hopping Spread Spectrum (THSS) and is a spread spectrum technique.
The THSS method is a time division multiplex in which the time slots for the individual transmission channels are varied in time. The spacing between the slots of a transmission channel is pseudo-random; sometimes shorter, sometimes longer. In order for the receiver to reassign the individual data from the slots to the transmission channels, the transmitting unit must transmit the pseudo-random pattern to the receiving unit.
With the THSS technique, several transmission channels can be transmitted over the same frequency, since a separate time slot is available for each one. The THSS technique thus also provides protection against unauthorized interception of the transmission channels because the information can only be intercepted if the receiver knows the pseudo-random pattern.