Data communication method for a set of hard-real time applications within a network

Abstract

A data communication method for a set of hard real-time applications with an associated set of predefined network requirements (PNR) is provided. The method comprises configuring the physical layer of the network with a set of static modulation parameters (SMPs) to guarantee the PNRs are met at worst-case operating conditions for the network. The method further comprises measuring the current network performance within the network based on a given network performance monitoring schedule and, whenever the current network performance exceeds the PNRs by predefined amounts, adjusting the physical layer of the network by selecting a set of dynamic modulation parameters (DMP's) to increase the bandwidth availability within the network. Advantageously, the invention further allows for the allocation of the excess bandwidth to a set of non-hard real-time applications, whenever the current network performance exceeds the PNR.

1 . Within a network, a data communication method comprising
 i. for a set of hard real-time applications with an associated set of predefined network requirements (PNR), configuring the physical layer of the network with a set of static modulation parameters (SMPs) to guarantee the PNRs are met at worst-case operating conditions for the network;   ii. measuring the current network performance within the network based on a given network performance monitoring schedule; and   iii. whenever the current network performance exceeds the PNRs by predefined amounts, adjusting the physical layer of the network by selecting a set of dynamic modulation parameters (DMP's) to increase the bandwidth availability within the network.   
   
   
       2 . The data communication method of  claim 1 , further comprising: whenever the current network performance exceeds the PNR, allocating the excess bandwidth to a set of non-hard real-time applications. 
   
   
       3 . The data communication method of  claim 1  wherein the communication within the network is based on a command/response protocol based on bus control. 
   
   
       4 . The data communication method of  claim 1  wherein the communication within the network is based on a priority signaling scheme among terminals of the network. 
   
   
       5 . The data communication method of  claim 1  wherein the monitoring schedule is periodic. 
   
   
       6 . The data communication method of  claim 3  wherein the command/response protocol is according to the 1553 standard. 
   
   
       7 . The data communication method of  claim 1  wherein the SMP's and the DMP's are OFDM parameters. 
   
   
       8 . The data communication method of  claim 1  wherein the adjustment of the physical layer of the network comprises adjustment of data modems of terminals within the network. 
   
   
       9 . The data communication method of  claim 1  wherein modulation parameters are selected from the group consisting of transmitter power, transmitter digital scaling, power spectral density, modulation level, modulation scheme, bits/tone of OFDM subcarriers, error correction scheme and convolutional code rate. 
   
   
       10 . The data communication method of  claim 1  further comprising whenever the current network performance exceeds the PNRs by predefined amounts, adjusting a network layer above the physical layer by selecting a set of higher layer dynamic modulation parameters (DMP's) to increase the bandwidth availability within the network. 
   
   
       11 . The data communication method of  claim 10  wherein the network layer above the physical layer is a Media Access Control layer. 
   
   
       12 . The data communication method of  claim 11  wherein the higher layer dynamic modulation parameters are selected from the group of frame size and overhead size. 
   
   
       13 . The data communication method of  claim 1  wherein the network is a managed network. 
   
   
       14 . The data communication method of  claim 1  further comprising using a message retransmit scheme whenever current network performance does not exceed the PNRs by predefined amounts and the network is configured based on dynamic modulation parameters. 
   
   
       15 . The data communication method of  claim 4 , wherein the message retransmit scheme comprises retransmiting signals within the network based on the set of DMP's in use, for a predetermined number of retries. 
   
   
       16 . The data communication method of  claim 15 , wherein the predetermined number of retries is dependent on the overhead of retries.