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.

Abstract: Gain variations during a packet can lead to significant performance degradation in communications systems that use high order quadrature amplitude modulation (QAM). A method and the associated apparatus track such variations in an OFDM system and completely eliminate any performance degradation. Gain estimation and compensation is employed with the use of pilot subcarriers in the payload of an OFDM data packet. Estimated pilot magnitude ratios are averaged, throughout the processing life of a packet, to yield accurate gain estimations. A gain compensation factor is used to adjust data carriers. An exclusion method is also employed to eliminate pilot carriers which contribute to noise.