1. A lamp assembly, comprising:a light source substrate comprising a first surface, a second surface and a plurality of light sources, wherein the first surface is opposite to the second surface, and the light sources are disposed on the first surface;
a circuit board electrically connected to the light source substrate, wherein a transmitting and receiving module is disposed on the circuit board, and the transmitting and receiving module has an antenna;
a lamp cover covering the light sources, wherein the lamp cover has an outer surface, an inner surface and a through hole, the inner surface is opposite to the outer surface, and the through hole extends from the inner surface to the outer surface, wherein the antenna passes through the through hole and extends outside the outer surface of the lamp cover; and
a fixing member disposed on the outer surface of the lamp cover, wherein the fixing member is configured to fix the antenna and comprises:
an extending portion parallel to the outer surface of the lamp cover, wherein the extending portion has an accommodating slot, and the accommodating slot is configured to accommodate the antenna; and
a positioning post vertically disposed on the extending portion, wherein the positioning post is inserted into a positioning hole of the lamp cover.