Certain aspects of the present disclosure provide procedures for transparent demodulation reference signal (DM-RS) design. According to certain aspects, a method of wireless communication by a base station (BS) is provided. The method generally includes transmitting one or more pilots based on at least one precoder used for transmitting data. The BS transmits the data based on the at least one precoder. A method by a user equipment (UE) includes receiving one or more pilots based on at least one precoder used for transmitting data on a channel. The UE estimates interference based on the one or more pilots and the UE decodes the data transmission based on the interference estimate.

A voice level comparator compares a level of a voice signal collected by a microphone with a VOX level. A transmission determination unit instructs a transmitter to transmit the voice signal, when the level of the voice signal is equal to or greater than the VOX level, based on a comparison result by the voice level comparator. A timer starts to measure an elapsed time from a point of time when a switch is operated. A VOX level selector seta a first VOX level as the VOX level when the elapsed time measured by the timer exceeds a reference elapsed time, and sets a second VOX level which is smaller than the first VOX level as the VOX level when the elapsed time measured by the timer stays within the reference elapsed time.

A semiconductor device includes an RF circuit and a microcontroller. The RF circuit has: a transmission unit generating a transmission signal; a reception unit generating a first generation signal and a second generation signal; and a transmission/reception loop-back switching unit switching between a first coupling state of coupling an output terminal of the transmission unit to a transmission antenna and coupling an input terminal of the reception unit to a reception antenna and a second coupling state of coupling an output terminal of the transmission unit to the input terminal of the reception unit. The microcontroller switches the transmission/reception loop-back switching unit to the second coupling state and executes a test of the RF circuit on the basis of the second generation signal when the transmission/reception loop-back switching unit is in the second coupling state and an output signal of a first sensor circuit.

A composite filter apparatus includes a common terminal, a transmission-side terminal, a reception-side terminal, a transmission filter, and a reception filter with a pass band higher than the pass band of the transmission filter. The transmission filter is connected between the common terminal and the transmission-side terminal and the reception filter is connected between the common terminal and the reception-side terminal. An inductor is provided between the common terminal and the reception filter in a path between the common terminal and the reception-side terminal. The resonant frequency of a parallel-arm resonator closest to the common terminal in the reception filter is lower than a high end frequency of the pass band of the transmission filter and is lower than the resonant frequencies of the other parallel-arm resonators in the reception filter.

Described herein are radio-frequency (RF) modules that include shielding for improved RF performance. The RF modules including a packaging substrate with a receiving system implemented thereon. The RF module includes a shield implemented to provide RF shielding for at least a portion of the receiving system. The receiving system can include any combination of pre-amplifier or post-amplifier bandpass filters, amplifiers, switching networks, impedance matching components, phase-shifting components, input multiplexers, and output multiplexers. The shielding can include a conductive layer within a conformal shielding on an upper side and side walls of the RF module. The shielding can be an overmold formed over the packaging substrate. The conductive layer can be connected to one or more ground planes. The packaging substrate can include contact features on an underside of the substrate for mounting an underside component.

A radio communication device is provided with a VOX function. A reception completion state determination unit determines whether or not a reception unit is in a state of completing reception. A timer starts to measure a predetermined time when the reception completion state determination unit determines that the reception unit is in the state of completing the reception. A VOX level selection unit sets a VOX level at which the VOX function determines that transmission is made to a first VOX level after the timer finishes measuring the predetermined time, and sets the VOX level to a second VOX level smaller than the first VOX level while the timer is measuring the predetermined time.

A radio communication device is provided with a VOX function. A reception completion state determination unit determines whether or not a reception unit is in a state of completing reception. A timer starts to measure a predetermined time when the reception completion state determination unit determines that the reception unit is in the state of completing the reception. A VOX level selection unit sets a VOX level at which the VOX function determines that transmission is made to a first VOX level after the timer finishes measuring the predetermined time, and sets the VOX level to a second VOX level smaller than the first VOX level while the timer is measuring the predetermined time.

A semiconductor switch includes a plurality of first terminals, a second terminal commonly provided for the plurality of first terminals, a plurality of first MIS switches provided between the plurality of the first terminals and the second terminal, respectively, configured to pass-through or cut-off a high frequency signal between the plurality of the first terminals and the second terminal, and formed on a SOI substrate, and a capacitor formed on the SOI substrate, connected between the second terminal and the plurality of the first MIS switches, and provided for the plurality of the first terminals commonly.

A radio communication device is provided with a VOX function. A reception completion state determination unit determines whether or not a reception unit is in a state of completing reception. A timer starts to measure a predetermined time when the reception completion state determination unit determines that the reception unit is in the state of completing the reception. A VOX level selection unit sets a VOX level at which the VOX function determines that transmission is made to a first VOX level after the timer finishes measuring the predetermined time, and sets the VOX level to a second VOX level smaller than the first VOX level while the timer is measuring the predetermined time.

A radio communication device is provided with a VOX function. A reception completion state determination unit determines whether or not a reception unit is in a state of completing reception. A timer starts to measure a predetermined time when the reception completion state determination unit determines that the reception unit is in the state of completing the reception. A VOX level selection unit sets a VOX level at which the VOX function determines that transmission is made to a first VOX level after the timer finishes measuring the predetermined time, and sets the VOX level to a second VOX level smaller than the first VOX level while the timer is measuring the predetermined time.