597 results about "RF front end" patented technology

An encoded information reading (EIR) terminal can comprise a microprocessor electrically coupled to a system / data bus, a memory communicatively coupled to the microprocessor, an EIR device, a multi-band antenna, and a wireless communication interface. The EIR device can be provided by a bar code reading device, an RFID reading device, or a card reading device. The EIR device can be configured to output raw message data containing an encoded message and / or output decoded message data corresponding to an encoded message. The wireless communication interface can comprise a radio frequency (RF) front end electrically coupled to the multi-band antenna. The RF front end can comprise a micro-electromechanical (MEMS) filter array including one or more band-pass filter. Each band-pass filter of the MEMS filter array can be electrically coupled to a bias voltage source or an oscillating signal source. The RF front end can be electrically coupled to an analog-to-digital (A / D) converter and / or to a digital-to-analog (D / A) converter. The wireless communication interface can be configured to transmit radio signals in two or more frequency regulatory domains and / or receive radio signals in two or more frequency regulatory domains. The multi-band antenna can in one embodiment be provided by a meta-material antenna.

Multiple power amplifiers in an RF front end are coupled to multiple antennas without diversity switching between the PAs and antennas. Diversity switches direct signals to broadcast by a selected antenna to a PA coupled to the selected antenna. Multiple LNAs are similarly coupled to the diverse antennas. Having one PA and LNA set for each antenna removes the need for diversity switching between the PA / LNAs and each antenna improving signal reception. In one embodiment, a single external PA performs broadcast functions and plural on-chip LNAs are used for reception. In another embodiment, phase shifters are coupled to each PA and LNA, which provide beam forming capability for broadcasts, and in phase signal combinations for received signals.

In an RF front-end having a plurality of signal paths connectable to an internal antenna or an external antenna, an antenna switch part is used to select either the internal or the external antenna. In the antenna switch part, two series switches are used to operatively connect to the same connection point in each signal path. These two series switches are separately connected to two different antennas for selecting one of the antennas in order to route the signals in that signal path. For providing further isolation between signal paths, each signal path can be connected to a shunt switch near the connection point. Only the shunt switch connected to the selected signal path is operated in an open position, all the other shunt switches are operated in a closed position.

Methods and devices are described for reducing receiver complexity in an RF front-end stage. In one exemplary implementation, a switch is used to connect a plurality of receive paths to a single input amplifier of a transceiver unit used the RF front-end stage. In another exemplary implementation, the switch has a tunable network which can be tuned with respect to various frequencies of operation of the receive path and associated RF signal.