Electronic device with shared multiband antenna and antenna diversity circuitry

An electronic device comprising:

• a housing;
• transceiver circuitry in the housing that handles wireless local area network radio-frequency signals at 5 GHz and radio-frequency signals at 2.4 GHz;
• an antenna structure in the housing that is used to simultaneously receive 5 GHz radio-frequency signals for the transceiver circuitry and transmit 2.4 GHz radio-frequency signals from the transceiver circuitry;
• and
• a cellular telephone transceiver and cellular telephone antenna in the housing.

An electronic device comprising:

• an antenna structure;
• wireless communications circuitry that transmits and receives radio-frequency signals with the antenna structure, wherein the radio-frequency signals include radio-frequency signals in a first communications band and radio-frequency signals in a second communications band;
• a diplexer coupled between the antenna structure and the wireless communications circuitry, wherein the diplexer has terminals respectively connected to:
• a first path that conveys the radio-frequency signals in the first communications band;
• a second path that conveys the radio-frequency signals in the second communications band;
• an antenna path coupled to the antenna structure;
• and
• bandpass filter circuitry that is coupled between the diplexer and the wireless communications circuitry.

A portable electronic device, comprising:

• an antenna structure having a first antenna and a second antenna;
• an antenna diversity switch that selectively switches the first and second antennas into use in response to antenna diversity control signals;
• radio-frequency transceiver circuitry that transmits and receives radio-frequency signals through the antenna diversity switch, wherein the radio-frequency signals include radio-frequency signals in a first communications band and radio-frequency signals in a second communications band;
• a diplexer coupled between the antenna structure and the radio-frequency transceiver circuitry, wherein the diplexer has terminals respectively connected to:
• a first path that conveys the radio-frequency signals in the first communications band;
• a second path that conveys the radio-frequency signals in the second communications band;
• an antenna path coupled to the antenna diversity switch;
• and
• a first bandpass filter that is interposed in the first path between the diplexer and the radio-frequency transceiver circuitry;
• and
• a second bandpass filter that is interposed in the second path between the diplexer and the radio-frequency transceiver circuitry.