a single sidelooking beam. Schemes A conventional beamformer can be a simple beamformer also known as delay-and-sum beamformer. All the weights of the antenna elements can have equal magnitudes. The beamformer is steered to a specified direction only by selecting appropriate phases for each antenna. If the noise is uncorrelated and there are no directional interferences, the signal-to-noise ratio of a beamformer with antennas receiving a signal of power , (where is Noise variance or Noise power), is: A null-steering beamformer is optimized to have zero response in the direction of one or more interferers. A frequency-domain beamformer treats each frequency bin as a narrowband signal, for which the filters are complex coefficients (that is, gains and phase shifts), separately optimized for each frequency. Evolved Beamformer The delay-and-sum beamforming technique uses multiple microphones to localize sound sources. One disadvantage of this technique is that adjustments of the position or of the number of microphones changes the performance of the beamformer nonlinearly. Additionally, due to the number of combinations possible, it is computationally hard to find the best configuration. One of the techniques to solve this problem is the use of genetic algorithms. Such algorithm searches for the microphone array configuration that provides the highest signal-to-noise ratio for each steered orientation. Experiments showed that such algorithm could find the best configuration of a constrained search space comprising ~33 million solutions in a matter of seconds instead of days. History in wireless communication standards Beamforming techniques used in cellular phone standards have advanced through the generations to make use of more complex systems to achieve higher density cells, with higher throughput. Passive mode: (almost) non-standardized solutions Wideband code division multiple access (WCDMA) supports direction of arrival (DOA) based beamforming Active mode: mandatory standardized solutions 2G – Transmit antenna selection as an elementary beamforming 3G – WCDMA: transmit antenna array (TxAA) beamforming 3G evolution – LTE/UMB: multiple-input multiple-output (MIMO) precoding based beamforming with partial space-division multiple access (SDMA) Beyond 3G (4G, 5G...) – More advanced beamforming solutions to support SDMA such as closed-loop beamforming and multi-dimensional beamforming are expected An increasing number of consumer 802.11ac Wi-Fi devices with MIMO capability can support beamforming to boost data communication rates. Digital, analog, and hybrid To receive (but not transmit), there is a distinction between analog and digital beamforming. For example, if there are 100 sensor elements, the "digital beamforming" approach entails that each of the