A method, apparatus and system for coherent beam combining (CBC) in high energy fiber laser (HEL) systems include generating a reference interference pattern of a signal source including at least two single-mode optical signals, capturing and evaluating the reference interference pattern, maximizing an intensity of the selected area of the captured, reference interference pattern, increasing a linewidth of the optical signals generating the reference interference pattern until the reference interference pattern is degraded, and adjusting a delay time of one of the at least two single-mode optical signals until the reference interference pattern is recovered, by adjusting a value of a delay of a delayed RF signal with a broaden linewidth to a respective EO linewidth broadening modulator in at least one channel of the at least two single-mode optical signals while evaluating the interference pattern on a display device.