Abstract: Receivers and methods of testing are described. A receiver includes a plurality of receiver channels, each including an amplifier for receiving a signal from an antenna and a mixer downstream of the amplifier. A test signal generating circuit is configured to generate test signals. A signal path connects the test signal generating circuit and each receiver channel and couples to each receiver channel at a coupling between the amplifier and a mixer. A test signal from the test signal generating circuit is injectable to the parts of the receiver channel downstream of the amplifier. The test signal may alternatively be injected into the entire receiver channel. The receivers and methods may be used in wireless systems, such as radar systems and radio systems.

Abstract: Receivers and methods of testing are described. A receiver includes a plurality of receiver channels, each including an amplifier for receiving a signal from an antenna and a mixer downstream of the amplifier. A test signal generating circuit is configured to generate test signals. A signal path connects the test signal generating circuit and each receiver channel and couples to each receiver channel at a coupling between the amplifier and a mixer. A test signal from the test signal generating circuit is injectable to the parts of the receiver channel downstream of the amplifier. The test signal may alternatively be injected into the entire receiver channel. The receivers and methods may be used in wireless systems, such as radar systems and radio systems.

Abstract: The invention provides a testing circuit for testing a connection between a chip and external circuitry. A current source is used to inject a DC current towards the connection to be tested from the chip side. On-chip ESD protection is provided giving a path between the connection to be tested and a fixed voltage line. A shunt path is also coupled to the connection to be tested on the external circuitry side. It is determined if the current source current flows through the ESD protection circuit, and this can be used to determine whether or not the connection to be tested presents an open circuit for the DC test current.

Abstract: The invention refers to an RF front-end (100) adapted to receive or transmit signals located in at least two separated frequency bands (100) comprising an input and an output and further comprising a first phase shifter (5) coupled to the input of the RF front-end (100); a second phase shifter (6) coupled to the output of the RF front-end (100); the first phase shifter (1) being coupled to the second phase shifter (2) via a first amplifier (3) and second amplifier (4), respectively.

Abstract: The invention refers to an RF front-end (100) adapted to perform either in a receiving mode or in a transmitting mode and adapted to receive or transmit signals located in at least two separated frequency bands, respectively comprising an input and an output and further comprising an input matching circuit (1) comprising a first input coupled to the input of the RF front-end (100), an output matching circuit (2) coupled to the output; the input matching circuit (1) being coupled to the output matching circuit (2) via respective first amplifier (3) and second amplifier (4), and a phase shifter (5) coupled either to the input of the RF front-end (100) in a receiving mode, or to the output of the RF front-end (100) in a transmitting mode.

Abstract: The invention provides a testing circuit for testing a connection between a chip and external circuitry. A current source is used to inject a DC current towards the connection to be tested from the chip side. On-chip ESD protection is provided giving a path between the connection to be tested and a fixed voltage line. A shunt path is also coupled to the connection to be tested on the external circuitry side. It is determined if the current source current flows through the ESD protection circuit, and this can be used to determine whether or not the connection to be tested presents an open circuit for the DC test current.

Abstract: The invention refers to an RF front-end (100) adapted to receive or transmit signals located in at least two separated frequency bands (100) comprising an input and an output and further comprising a first phase shifter (5) coupled to the input of the RF front-end (100); a second phase shifter (6) coupled to the output of the RF front-end (100); the first phase shifter (1) being coupled to the second phase shifter (2) via a first amplifier (3) and second amplifier (4), respectively.

Abstract: The invention refers to an RF front-end (100) adapted to perform either in a receiving mode or in a transmitting mode and adapted to receive or transmit signals located in at least two separated frequency bands, respectively comprising an input and an output and further comprising an input matching circuit (1) comprising a first input coupled to the input of the RF front-end (100), an output matching circuit (2) coupled to the output; the input matching circuit (1) being coupled to the output matching circuit (2) via respective first amplifier (3) and second amplifier (4), and a phase shifter (5) coupled either to the input of the RF front-end (100) in a receiving mode, or to the output of the RF front-end (100) in a transmitting mode.

Abstract: A multi-mode radio module (22) comprises a terminal (11) for connection to an antenna (10). A transmitting branch (DCS/PCS) and a branching circuit are coupled to the terminal (11). The branching circuit comprises at least a first and a second branch for receiving signals in first and second frequency bands (DCS, PCS), respectively. Each of the first and second branches comprise, respectively, a phase shifting circuit (PS1, PS2), a BAW or SAW band pass filter (RXF2, RXF3) coupled to the phase shifting circuit, the bandwidth of the filter being selected to pass a wanted signal in one of the first and second frequency bands but reject an unwanted signal in the other of the second and first frequency bands, and a low noise amplifier (LNA2, LNA3) coupled to an output of the band pass filter. The response of each of the band pass filters (RXF2, RXF3) is phase shifted to present an open circuit at the wanted frequency in the other branch.

Abstract: The transmitter and/or receiver module comprises a dipole antenna (28) and a matching circuit (26) matching the output impedance of the module to the antenna impedance, a switch circuit (24) for switching between received and transmitted signals, a power amplifier (30) for amplifying the transmitted signal, and a low-noise receiver amplifier (32) for amplifying the received signal, wherein the matching circuit (26) and the antenna (28) are designed to provide a bandpass filter function for the module. Differential signals are provided from the transmitter power amplifier (30) to the antenna (28) and/or from the antenna (28) to the receiver amplifier (32) without conversion of the differential signals to single-ended signals.