Complementary Sequences - Definition

Definition

Let (a0, a1, ..., aN − 1) and (b0, b1, ..., bN − 1) be a pair of bipolar sequences, meaning that a(k) and b(k) have values +1 or −1. Let the aperiodic autocorrelation function of the sequence x be defined by

Then the pair of sequences a and b is complementary if:

for k = 1, ..., N − 1.

Or using Kronecker delta we can write:

where C is a constant.

So we can say that the sum of autocorrelation functions of complementary sequences is a delta function which is an ideal autocorrelations for many applications like radar pulse compression and spread spectrum telecommunications.

Read more about this topic:  Complementary Sequences

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