초록 ▼

A system for time division multiplexed communication over a single frequency band in which guard time overhead is reduced by active adjustment of reverse link transmission timing as a function of round trip propagation time. In one embodiment, during a first portion of a time frame, a base station i

A system for time division multiplexed communication over a single frequency band in which guard time overhead is reduced by active adjustment of reverse link transmission timing as a function of round trip propagation time. In one embodiment, during a first portion of a time frame, a base station issues a single burst segmented into time slots comprising data directed to each user station. After a single collective guard time, the user stations respond, one by one, in allocated time slots on the same frequency as the base station, with only minimal guard times between each reception. In order to prevent interference among the user transmissions, the base station measures the round trip propagation time for each user station and commands the user stations to advance or retard their transmission timing as necessary. To establish the initial range of a new user station, a short message is sent by the new user station during the collective guard portion (or, alternatively, during an available time slot), from which the base station calculates the propagation delay and hence the distance of the user station. Messages sent from the base station to the user stations may be interleaved so as to reduce the effects of potential noise or interference.

대표청구항 ▼

1. A system for communication comprising a base station, a plurality of user stations, and a transmission format;said transmission format comprising a plurality of time frames of equal duration, each of said time frames comprising a base transmission portion, a collective guard portion, and a user t

1. A system for communication comprising a base station, a plurality of user stations, and a transmission format;said transmission format comprising a plurality of time frames of equal duration, each of said time frames comprising a base transmission portion, a collective guard portion, and a user transmission portion, said collective guard portion located between said base transmission portion and said user transmission portion, each base transmission portion comprised of a plurality of base time slots and each user transmission portion comprised of a plurality of user time slots; said base station comprising the capability to transmit a plurality of sub-messages in each of said base time slots of said base transmission portion of a time frame, each said sub-message transmitted in a base time slot transmitted to a different user station, and in which one or more sub-messages from a plurality of base time slots of a time frame comprises a base-to-user message for a user station; and a user station of said plurality of user stations comprising the capability to transmit a user-to-base message in a user time slot of said user transmission portion of a time frame.