Antenna directivity effect on the delay spread at millimeter-wave

Millimeter-wave band has been using for high-speed line of sight transmission in short range and there is no problem due to delay spread. But if it is used in indoor to connect an access point(AP) to terminals of WLAN, the delay spread made by multipath reflections limits the transmission speed. Typically, antenna beamwidth is the wider, delay spread is the bigger and it is also equally applicable at millimeter-wave band. Therefore, the delay spread characteristics according to antenna beamwidth is important to set a WLAN at millimeter-wave in indoor. To study the delay spread characteristics at millimeter-wave band, the propagation characteristics according to antenna beamwidth were measured in the empty office room with only an partition for non line of sight(NLOS). The simulation results compare with measured data to obtained the accuracy of simulation. Finally the statistical value of delay spread characteristics according to antenna beamwidth were obtained by simulation at indoor office line of sight(LOS).