Patent ID: 7792492

Claim:
A method of operating a data communication system, the data communication system including at least a first communication controller and at least a first node, the method comprising: transmitting a random access connection request signal from the first node to the first communication controller in a first slot indicating that the first node can receive messages transmitted from the first communication controller; receiving a connection request response signal from the first communication controller transmitted to the first node in response to the random access connection request signal, said connection request response signal providing information indicating that the first node can transmit a reserve access request signal in a second slot in order to subsequently transmit a message to the first communication controller; receive an aligning signal which enables the first node to transmit the reserve access request signal; transmitting the reserve access request signal in the first slot in response to the connection request response signal from the first communication controller; receiving a grant signal from the first communication controller subsequent to transmission of the reserve access request signal, said grant signal including information indicating resources have been allocated for transmission of message data packets to the first communication controller; transmitting the message data packets from the first node in response to the grant signal; wherein the message data packets comprise multiple data packets, wherein at least one the message data packets contain information related to a count value, wherein the final data packet from the multiple data packets contains terminal indication information indicating that termination of the message data packets has occurred; wherein a subsequent reserve access request signal from a second node provided in a third slot assigned to the second node can be transmitted during transmission of the message data packets by the first node; and wherein the aligning signal is received on first frequency, the reserve access request signal is transmitted on a second frequency, the grant signal is received on a third frequency and the message data packets are transmitted on a fourth frequency, wherein the first frequency, the second frequency, the third frequency and the fourth frequency are differing frequencies, wherein the aligning signal is distinct from the first grant signal.