Multiple Access Digital Communicating Method In Ultra-Wideband Radio Access Networks

A digital communication method in an uplink of a UWB communication system, the method comprising:

• summing energies of received signals at time slots which are assigned to the respective user nodes through orthogonal time hopping patterns;
• comparing the summed energy with a predetermined critical value;
• and
• when the summed energy is greater than the critical value, judging that the user node has transmitted data.

A digital communication method, comprising the steps of:

• allowing user nodes to attempt multiple accesses by a scheduling based orthogonal time division method according to data transmission rates of services requested by the respective user nodes;
• allowing user nodes to attempt multiple accesses by an orthogonal time hopping method using orthogonal time hopping patterns;
• and
• classifying the user nodes into at least one group, and attempting communication by groups in a mixed mode of the orthogonal time division method and the orthogonal time hopping method.

A digital communication method in a contention access period in case that plural nodes set up communication concurrently with a communication network which has been in an initialized state, the method comprising the steps of:

• dividing the entire contention access period into small time slots;
• dividing the respective time slots into uplink mini-slots requesting communication setup and downlink mini-slots for giving an ACK thereto;
• and
• in a node in need of communication setup, requesting the communication setup by randomly using one of the plural uplink mini-slots.

A digital communication method in an uplink of a UWB communication system, comprising the steps of:

• receiving data symbols from respective nodes, in which the data symbols are transmitted according to respective orthogonal time hopping patterns;
• checking whether there is a collision of the orthogonal time hopping patterns;
• and
• decoding the data symbols depending on whether data symbols of nodes involved in the collision of the orthogonal time hopping patterns are the same.