Koninklijke Philips Corporation N.V.

U.S. Philips Corporation

St-ericsson Sa

Danish Ali

In a UMTS/GSM receiver with EDGE services capability, a data sequence incorporating PSK symbols is separated into bits which are assigned confidence values and input to convoluntional decoder () to provide improved decoding.

Signal processing method and apparatus using bit confidence values

A Rake receiver suitable for receiving, for example, direct sequence CDMA signals, in which the pilot code used to correlate the received signal in each Rake finger (RF, RF, RFN) is interpolated prior to the correlation.

Rake receiver

A Sigma-Delta modulator( ) comprises a signal put( ) coupled to a forward filter comprising a series connection of a plurality of N summing stages( ), where N is an integer of at least , alternating with a corresponding plurality of integrating stages( ) and an analogue to digital converter(ADC)( ) having an input coupled to an output of the Nth integrating stage( ) and an output. A feedback filter comprises a feedback coupling from the output of the ADC( ) to a digital to analogue converter(DAC)( ) which is coupled to an input of each of the summing stages by way of respective weights( ). Control means( ) including switching means ( ) are provided for changing the order of the modulator. To reduce the order and increase the bandwidth, the control means by-passes the first( ) of the integrating stages and uses the second( ) of the integrating stages as a first of the integrating stages and vice versa to increase the order and decrease the bandwidth.

Variable order sigma-delta modulator

A radio receiver has an input coupled to first and second quadrature related low-IF frequency translation stages generating IF signals at substantially half the channel bandwidth or channel spacing. The IF signals which may be optionally filtered in a pre-filter, for example a polyphase filter, are applied to first and second cross-coupled continuous time, low pass Sigma-Delta modulators. The modulators include transconductor-capacitor integrators, all but the first integrators of which are cross-coupled by gyrators set to resonate at the IF frequency. Outputs of the Sigma-Delta modulators include 1 bit oversampled signals. The oversampled signals may be filtered in first decimation stages which provide anti-aliasing. The decimated signals are derotated and decimated in a second decimation means to provide outputs at base band. The base band outputs are equalized and demodulated to provide an output. The input signal may be frequency translated to zero IF and then filtered in low pass filters.

Radio receiver

A transmitter having an integratable quadrature oscillator network for simultaneously producing a sine wave and a cosine wave. The digital direction of rotation (whether the frequency is positive or negative) input is slow rate limited (R, C,) and fed into a low gm transconductor (MOS,MOS,) to softly switch between two pairs of transconductor amplifiers (TR,TR,and TR,TR,) which together with two capacitors (C,C,) form quadrature oscillators of opposite direction of rotation. By softly switching the quadrature oscillators out-of-band emissions are minimized in a subsequent mixing with a carrier signal to generate a frequency modulated signal.

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South Croydon, United Kingdom

Danish Ali