Patent ID: 7885354

Claim:
A method implemented within a near vertical incidence skywave (“NVIS”) communication system comprising: transmitting pilot signals and data signals from a first plurality of directional antennas of a multi-antenna transceiver at near vertical incidence within a frequency range to cause the pilot signals and data signals to reflect off of the ionosphere towards a near vertical incidence skywave (“NVIS”) receiver system having a second plurality of directional antennas; estimating channel state information (“CSI”) for the communication channels using the pilot signals, and responsively generating channel characterization data comprising at least N*M components, where N represents a number of the first plurality of directional antennas of the multi-antenna transceiver and M represents a number of the second plurality of directional antennas of the NVIS receiver system, wherein the N antennas of the multi-antenna transceiver are used to communicate with the M antennas on the NVIS receiver system, each of the N*M components defining a gain over each transmission path between each one of the N antennas of the multi-antenna transceiver and each one of the M antennas on the NVIS receiver system; storing the channel characterization data including the N*M components; receiving a data stream to be transmitted wirelessly over one or more communication channels in response to a client request; coding the data stream with space-time coding techniques to create multiple statistically independent pre-coded data streams, wherein coding the data stream with space-time coding techniques comprises using each of the N*M components of the channel characterization data to pre-code each of the data streams prior to transmission from each of the antennas; mapping each of the pre-coded data streams to a particular antenna of the N directional antennas of the multi-antenna transceiver; and thereafter transmitting the multiple pre-coded data streams and additional pilot signals from each of the N directional antennas of the multi-antenna transceiver at near vertical incidence within a frequency range to cause the transmitted pre-coded data streams and pilot signals to reflect off of the ionosphere towards the near vertical incidence skywave (“NVIS”) receiver system having the M directional antennas; continuing to measure the characteristics of the communication channels during transmission of the pre-coded data streams on a sub-one second basis to arrive at sub-one-second estimates for CSI and, in response, continually adjusting each of the N*M components of the channel characterization data; and continually adjusting the coding of the data streams between each one of the N antennas of the multi-antenna transceiver and each one of the M antennas on the NVIS receiver system on a sub-one-second basis based on the continually adjusted N*M components.