Renesas Technology Corp.

Ttpcom Limited

Hitachi, Ltd.

Thomson Licensing

Tipcom Limited

Thomson Licensing S.a.

Ttp Com Limited

Patrick Wurm

David Freeborough

Robert Astle Henshaw

Kazuhiko Hikasa

Ryoichi Takano

Jean-Yves Le Naour

Yasuyuki Kimura

Patrice Hirtzlin

Noriyuki Kurakami

Kazuhisa Okada

Hiroshi Hagisawa

Taizo Yamawaki

Kenji Toyota

Hisayoshi Kajiwara

In a polar loop based radio-communications apparatus having a phase control loop for controlling the phase of a carrier outputted from an oscillator for transmission, and an amplitude control loop for controlling the amplitude of a transmission output signal outputted from a power amplification circuit, the phase control loop is first started while maintaining the amplitude control loop in an off state at the outset of transmission, and the amplitude control loop is started after stabilizing the phase control loop.

Semiconductor integrated circuit for communication, radio-communication apparatus, and transmission starting method

A transmitter adopting a polar loop system including a phase control loop for controlling the phase of a carrier signal outputted from a transmitting oscillator and an amplitude control loop for controlling the amplitude of a transmitting output signal outputted from a power amplification circuit, and designed to be capable of performing transmission using a GMSK modulation mode and transmission using an 8-PSK modulation mode. In the transmitter, the phase control loop is shared as a phase control loop for use in the GMSK modulation mode and a phase control loop for use in the 8-PSK modulation mode. A component similar to any one of components constituting a loop filter is provided in parallel therewith so that the component can be connected or disconnected in accordance with the modulation mode, for example, by use of a switching element.

Transmitter and semiconductor integrated circuit for communication

In a transmitter of polar-loop architecture having a phase control loop and an amplitude control loop, as loop filters for controlling a loop band of the amplitude control loop, a first filter with lag-lead characteristics (secondary or more filter including a capacitor and a resistor) and a second filter of a perfect integrator type (filter including only a capacitor) are employed, and current-output type circuits are connected to respective front stages of the first and second filters.

Transmitter and wireless communication apparatus using the transmitter

A polar loop based radio telecommunication apparatus which has a phase control loop for controlling the phase of a carrier outputted from an oscillator for transmitter, and an amplitude control loop for controlling the amplitude of a transmission output signal outputted from a power amplifier circuit, wherein precharge means is provided on a forward path from a current source, through the power amplifier circuit, to a detection circuit, forming the amplitude control loop, for rapidly increasing a control voltage for the power amplifier circuit to a power threshold upon starting transmission.

Apparatus for radio telecommunication system and method of building up output power

In a radio communication system having a phase control loop for phase modulation and an amplitude control loop for amplitude modulation and being capable of time divisional transmission and reception under a predetermined time management, when transmission in a first mode is switched to transmission in a second mode or when transmission in the second mode is switched to transmission in the first mode, the output level of the power amplifier is lowered once to a predetermined level higher than the level when transmission related circuits are activated, and thereafter the output level of the power amplifier is again ramped after the settings have been changed but without starting of a transmission oscillator, establishing of the phase control loop and the amplitude control loop.

Method of ramping up output level of power amplifier of radio communication system, communication semiconductor integrated circuit, and radio communication system

The invention provides a simple solution for a broadband transmitter/receiver for which the working bandwidth is split into at least two non-contiguous sub-bands. The invention uses a filtering meanswhich comprises at least two band-pass filtersandprovided with switching meansandThe use of two switched filtersandmakes it possible to use a single synthesizerto scan two sub-bands of the working bandwidth. The frequency synthesizeroperates for one sub-band in supradyne mode and for the other sub-band in infradyne mode. In a variant, the invention uses a third filter and divides the bandwidth into three sub-bands.

Radiofrequency transmitter and/or receiver

Wireless communication apparatus having a phase control loop shared by first and second modulation modes and an amplitude control loop

An RF signals amplification block receives a first RF signal, and comprises means of amplification of this first RF signal so as to deliver a second, amplified, RF signal. This signal must be amplified by a predetermined nominal power so as to be delivered at the output of the block. The block comprises means of measurement of the power of the second, amplified, RF signal, means of coupling the amplified RF signal to a first output of the block, a control signal generated by a central processing unit for controlling the coupling means. The invention also relates to an RF signals transmission device intended to be arranged at the focus of RF signals focusing means comprising a block according to the invention and an RF signals transmission antenna/terminal. Particular application to the tracking of nonsynchronous satellites.

RF signal amplifier unit, RF signal transmission device and RF signal transmitting terminal-antenna

Semiconductor integrated circuit for communication, radio-communications apparatus, and transmission starting method

A mobile communication system has a mobile phone in which a voltage is set corresponding to the characteristic variation of a PA even when a PA having characteristic variation is used. The mobile phone employs a polar loop method, which comprises an antenna () for transmission and reception of signal waves; an antenna switch () for switching the transmission mode and the reception mode; a BBLSI () having a function to control the transmission and reception; an RFIC () having a function for modulating and demodulating the transmitted and received signals; and a PA () for amplifying up to the target output power by means of the amplitude modulation at the time of the transmission.

Apparatus for mobile communication system which performs signal transmission by amplitude modulation and phase modulation

Transmitter having a phase control loop whose frequency bandwidth is varied in accordance with modulation modes

A polar-loop wireless communication apparatus includes, on a forward path between an amplitude detector and a power amplifier which constitute an amplitude control loop, a variable gain amplifier and a switch to change characteristics of a loop filter to output a frequency bandwidth of the amplitude control loop to an order less than an order for normal operation. The system is operated with the characteristics set to the lower order to measure outputs from the power amplifier to calibrate the output power of the power transmitter, and the register is operated with the characteristics set to the higher order to measure the open loop gain of the amplitude control. According to results of the calculation, data to correct gain characteristics of the variable gain amplifier with respect to an output control signal is stored in a nonvolatile memory of a baseband circuit.

Communication semiconductor integrated circuit, a wireless communication apparatus, and a loop gain calibration method

An antenna circuit for a mobile telecommunication device. The circuit comprises a power amplifier for amplifying, in use, a signal to be transmitted. An antenna transmits signals output from the power amplifier. Switching means introduces, dependent upon the gain setting of the power amplifier, an attenuator between the output of the power amplifier and the antenna.

Antenna circuitry

The invention comprises a low-noise amplifier of the type comprising a transistor exhibiting a saturation phase for signals of high amplitude. According to the invention, at the output of the amplifier is arranged a load impedance referring back to this output an optimal impedance for maximizing the power at the output of the transistor and an open circuit in the reception frequency band. Thus, the entire parasitic signal is &ldquo;boxed in&rdquo; by the load impedance. Particular application in the field of bidirectional transmissions, especially transmission systems linking a terminal comprising the device according to the invention with at least one satellite or a terrestrial base station.

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Comberton, United Kingdom

Patrick Wurm