Radio frequency (rf) communications system having rf nodes that determine a despreading sequence and phase and timing offsets for frequency agility

A radio frequency (RF) communications system comprising:

• a first RF node configured to
• transmit data including a new frequency of operation, and
• transmit a sequence of pilot symbols spread with a spreading code sequence;
• and
• a second RF node configured to
• receive an incoming signal from the first RF node comprising at least the sequence of pilot symbols,
• perform despreading for N sample offset delays to generate N despreading sequences for the sequence of pilot symbols, a starting position of the sequence of pilot symbols being within N samples,
• perform a cross-correlation to select a strongest despreading sequence from the N despreading sequences, and determine a phase offset and timing offset,
• process the incoming signal based upon the strongest despreading sequence, phase offset and timing offset, and
• switch to the new frequency of operation.

A method of radio frequency (RF) communications comprising:

• operating a first RF node to
• transmit data including a new frequency of operation, and
• transmit a sequence of pilot symbols spread with a spreading code sequence;
• and
• operating a second RF node to
• receive an incoming signal from the first RF node comprising at least the sequence of pilot symbols,
• perform despreading for N sample offset delays to generate N despreading sequences for the sequence of pilot symbols,
• perform a cross-correlation to select a desired despreading sequence from the N despreading sequences, and determine a phase offset and timing offset,
• process the incoming signal based upon the desired despreading sequence, phase offset and timing offset, and
• switch to the new frequency of operation.