Antenna system and mobile terminal

An antenna system, comprising:

• a metal rear cover, a first feeding point and a system ground, wherein a U-shaped slot is arranged at a bottom of the metal rear cover, and the U-shaped slot divides the metal rear cover into a radiation portion and a grounding portion, the grounding portion is connected to the system ground, the radiation portion comprises a first end and a second end, and both the first end and the second end are connected to the grounding portion, a breaking joint is defined at the radiation portion, and the radiation portion is electrically connected to the first feeding point, so as to form a main antenna,
• wherein the main antenna has a first working frequency band, a second working frequency band and a third working frequency band, wherein the first working frequency band is 700 MHz-960 MHz, the second working frequency band is 1710 MHz-2700 MHz, and the third working frequency band is 3300 MHz-3800 MHz,
• wherein the first feeding point and the breaking joint divide the radiation portion into a first section, a second section and a third section, wherein the first section is a portion of the radiation portion from the first end to the first feeding point, the second section is a portion of the radiation portion from the first feeding point to the breaking joint, and the third section is a portion of the radiation portion from the breaking joint to the second end, and
• wherein a main radiator of the first working frequency band comprises the first section and the second section, a main radiator of the second working frequency band comprises the second section and the third section, and a main radiator of the third working frequency band comprises the first section, the second section and the third section.