Low-complexity beam alignment by directional phase in 5G and 6G

A method for a first wireless entity to determine an alignment direction toward a second wireless entity, relative to the first wireless entity, the method comprising:

• a) transmitting, by the first wireless entity, a first beam comprising a wide beam configured to span an angular range between a first angle and a second angle;
• b) wherein the first beam comprises a first phase distribution which is modulated, at the first angle, according to a first phase value, and is modulated, at the second angle, according to a second phase value;
• c) wherein the first phase distribution varies monotonically, from the first phase value to the second phase value, as the angle ranges from the first angle to the second angle;
• d) receiving, from the second wireless entity, a reply message indicating a measured phase value, measured by the second wireless entity upon receiving the first beam;
• and
• e) calculating, according to the first and second phase values and the first and second angles, and the measured phase value, the alignment direction toward the second wireless entity relative to the first wireless entity.