Predictive signal cancellation for extracting 1 Mb/s MIL-STD-1553 component from composite high performance 1553 signal

An interference cancellation method for canceling interference of 1553 signals comprising the steps of:

• acquiring from a data bus a sampled signal, the sampled signal comprising non- 1 Mb/s 1553 encoded data and 1 Mb/s 1553 encoded data;
• synthesizing the 1 Mb/s 1553 encoded data within the sampled signal to produce synthesized 1 Mb/s 1553 data;
• producing a variant of an interfering signal based on the sampled signal;
• and
• subtracting the variant of the interfering signal from the sampled signal and producing an output signal with a substantially cancelled 1 Mb/s 1553 component.

A 1553 communication system comprising:

• a data bus configured to carry a signal having a 1 Mb/s 1553 component and a non-1 Mb/s 1553 component;
• a unit configured to separate a first component and a second component from the signal on the data bus, the first component including mostly the 1 Mb/s 1553 component within a first frequency band, and the second component including most of the non-1 Mb/s 1553 component within a second frequency band;
• a synthesizing circuit configured to extract from the first component a synthesized 1 Mb/s 1553 signal;
• and
• an interference canceller configured to generate a variant of the 1 Mb/s 1553 component within the second frequency band based on the synthesized 1 Mb/s 1553 signal and the second component, to subtract the variant of the 1553 component within the second frequency band from the second component and to produce an output including mostly a non-1 Mb/s 1553 component.

A 1553 signal cancellation system for a 1553 communication system having a data bus carrying a combined signal that includes a 1553 signal and a High Performance 1553 signal, the cancellation system comprising:

• an input configured to receive the combined signal from the data bus;
• a unit, connected to the input, configured to extract the 1553 signal and to output synthesized 1553 data;
• and
• a cancellation circuit comprising:
• a unit configured to receive the synthesized 1553 data and to produce a cancelling signal;
• and
• a cancellation unit configured to subtract the cancelling signal from the combined signal to produce an output signal.

A method for cancelling non-High Performance 1553 signals from a signal in a 1553 data communication system, the method comprising the steps of:

• acquiring from a data bus a combined signal comprising High Performance 1553 encoded data and non-High Performance 1553 encoded data;
• synthesizing the non-High Performance 1553 encoded data to produce synthesized non-High Performance 1553 data;
• producing a cancelling signal based on the synthesized non-High Performance 1553 data;
• and
• subtracting the cancelling signal from the combined signal and producing an output signal that has the non-High Performance 1553 signals substantially cancelled therefrom.

In a 1553 communication system having a data bus carrying combined signals that include a non-High Performance 1553 component and a High Performance 1553 component, a system for cancelling the 1553 component from the combined signals comprising:

• a unit configured to separate from the combined signals into a first component and a second component, the first component including mostly the non-High Performance 1553 component within a first frequency band, and the second component including mostly the non-High Performance 1553 component and the High Performance 1553 component within a second frequency band;
• a unit configured to extract from the first component a non-High Performance 1553 synthesized signal;
• and
• a unit configured to generate a non-High Performance 1553 component within the second frequency band based on the 1553 synthesized signal, to subtract the generated non-High Performance 1553 component within the second frequency band from the second component and to produce an output signal including mostly a High Performance 1553 component.

A method employed by a terminal in a 1553 system for processing a 1553 signal from a received communication that may have a non-High Performance 1553 component and a High performance 1553 component, the method comprising:

• synthesizing a non-High Performance 1553 signal for use in the 1553 system when no High performance 1553 component is present in the communication, comprising:
• (a) receiving a non-High Performance 1553 message from a terminal in the system;
• (b) determining an identity of a terminal that transmitted the non-High Performance 1553 message;
• (c) detecting positive and negative zero-crossings of the non-High Performance 1553 message;
• (d) selecting one of a group of stored digitized waveform signals responsive to each zero crossing, the selected digitized waveform signals being associated with the detected terminal and associated with the position of each bit of the message;
• separating a non-High Performance 1553 component from the High performance 1553 component when both of the components are received in the communication;
• passing the received communication having both the non-High Performance 1553 component and the High Performance component through a filter to pass only the High Performance component and certain harmonics of the non-High Performance 1553 component;
• and
• subtracting a synthesized version of the non-High Performance 1553 signal from the filtered received communication having both the 1553 component and the High Performance component.

A method employed by a terminal in a 1553 system for processing a 1553 signal of a received communication that has a non-High Performance 1553 component and a High performance 1553 component, the method comprising:

• separating a portion of the non-High Performance 1553 component from the received communication;
• passing the received communication through a filter to pass only the High Performance component and certain harmonics of the non-High Performance 1553 component;
• and
• subtracting a synthesized version of the non-High Performance 1553 signal from the filtered received communication.