Abstract: A wireless electronic device may include switching circuits that perform time division duplexing by toggling between a first configuration in which radio-frequency signals received from antennas are routed to the transceivers and a second configuration in which the antennas are coupled to antenna switching circuitry. The antenna switching circuitry may receive radio-frequency transmission signals from the transceivers and route the transmission signals to a selected one of the antennas. The antenna switching circuitry may be controlled by control circuitry such as baseband circuitry and/or storage and processing circuitry on the device. The antenna switching circuitry may be controlled to accommodate antenna transmit diversity without affecting reception of radio-frequency signals, because the switching circuits that perform time division duplexing may form signal reception paths that are unaffected by the configuration of the antenna switching circuitry.

Abstract: A wireless electronic device may be used to communicate using multiple wireless standards in adjacent frequency bands. The wireless standards may include Wi-Fi® and cellular standards such as Long Term Evolution (LTE). The wireless electronic device may be provided with wireless communications circuitry that handles Wi-Fi® and cellular signals in adjacent frequency bands such as the Wi-Fi® 2.4 GHz frequency band and LTE bands 38 and 40. The wireless communications circuitry may include a triplexer interposed between transceiver circuitry and an antenna. The triplexer may be used to handle radio-frequency signals in adjacent frequency bands by separating the radio-frequency signals into signals associated with each frequency band. The triplexer may include filters that each pass signals in a respective one of the frequency bands between the transceiver circuitry and the antenna.