Radio frequency system and communication device

A radio frequency (RF) system comprising:

• a flexible circuit board having a notch;
• a first antenna module disposed on the flexible circuit board and covering the notch, the first antenna module comprising a first carrier, a first antenna element disposed on or in the first carrier, and a first conductive member between the first carrier and the flexible circuit board;
• and
• a RF chip disposed in the notch.

A communication device comprising:

• a housing;
• a first radio frequency (RF) system and a second RF system, respectively located at a first position and a second position in the housing, each of the first RF system and the second RF system comprising:
• a flexible circuit board having a first surface and a second surface, wherein the first surface and the second surface are located at different sides of the flexible circuit board;
• a first antenna module disposed on the first surface of the flexible circuit board, the first antenna module comprising a first carrier, a first antenna element disposed on or in the first carrier, and a first conductive member between the first carrier and the flexible circuit board;
• and
• a RF module disposed on the second surface of the flexible circuit board and electrically connected to the first antenna element through the flexible circuit board, the first conductive member and the first carrier;
• a main board;
• and
• a connection element electrically connecting the flexible circuit board and the main board.