# Delay and sum Beamforming

What is the difference between the weight vector (w) and the steering vector a(θ)?

I initially assumed they were the same thing, but the literature seems to be to be a bit fuzzy with this (or maybe its just me).

## 1 Answer

They're essentially the same, with the steering vector typically representing phase shifts (==delays) using complex numbers from the unity circle, and the weight vector often containing real values to scale the samples. In practice, both can be unified into one and hence, the terms are sometimes used interchangeably. Also note that for many algorithms, the individual amplitude of the samples doesn't matter, and hence, the steering vector's magnitudes can be chosen arbitrarily (as long as non-zero).

• In not sure I understand your last sentence, Marcus. It implies that I can select all the weights to be zero and still have a functioning array. – Peter K. Oct 7 '16 at 0:53
• Ha, @PeterK., thanks for reading precisely; will account for that. – Marcus Müller Oct 7 '16 at 13:30