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[nurul]

Hello,

what is the differences between analog and digital beamforming? is it only one has ADC in RF level while the other one has ADC in the baseband level?

one more, adaptive beamforming. adaptive beamforming means that the main beam of the antenna can be changed to adapt with the environment, correct? adaptive beamforming is categorized under digital or analog beamforming?

thanks a lot

[Schubert]

Digital beamforming uses a discrete set of weights: i.e. quantized values that are represented by a set of bits.

Analog beamforming uses an analog weight - it isn't confined to a specific set of values (i.e. continuous). Note that analog beamforming may not have an ADC at all - it can be used with analog modulation (for instance, AM signals).

Adaptive beamforming can be digital or analog - anything that changes in response to the environment. Even if there are only two possible beam patterns, this could be considered digital beamforming.

[nurul]

thanks Schubert.

If i want to apply LMS algorithm to determine the phase shift of an antenna array, that means I'm manitpulating its signal processing system and it's categorized under digital beamforming, correct?

and what if the weights aren't discrete?

thanks again for the reply

[Schubert]

"If i want to apply LMS algorithm to determine the phase shift of an antenna array, that means I'm manitpulating its signal processing system and it's categorized under digital beamforming, correct? "

- How does manipulating "its signal processing system" mean the beamforming is digital? That doesn't make any sense. The weights have to be discrete (quantized, bit-mapped, etc) to be digital. LMS is an intrinsically analog weighting system.