Back to results
US 7,095,997 B2Granted
Direct-conversion receiver for a communication system using a modulation with non-constant envelope
AssigneeSTMicroelectronics S.r.l.
InventorPatrick Conti
Life of this patent
Estimating the term…
Abstract
A direct-conversion receiver includes an analog stage for receiving an incident signal from a transmission channel, mixers and programmable-gain amplifiers. The receiver further includes at least one compensation module having input and output terminals respectively connected between the output of the mixers and the input of the programmable-gain amplifiers. The compensation module compensates for both a static DC voltage offset and a possible dynamic DC voltage offset of the analog stage.
Claims29
A direct-conversion receiver for a communication system using modulation having a non-constant envelope, the direct-conversion receiver comprising:
- an analog stage for receiving a signal from a transmission channel, said analog stage comprising
- transposition means for transposing the signal to a baseband signal,
- at least one compensation module connected to said transposition means for compensating the baseband signal for static and dynamic DC voltage offsets within said analog stage, and
- programable-gain amplification means connected to said at least one compensation module for amplifying the compensated baseband signal;
- wherein said at least one compensation module further comprises
- an input terminal and an output terminal,
- first means connected to the input terminal for determining an envelope of an AC component of the baseband signal,
- second means connected to the input terminal for determining an envelope of the baseband signal,
- first subtraction means having a first input connected to an output of said first means, and a second input connected to an output of said second means, and
- second subtraction means having a first input connected to the input terminal, a second input connected to an output of said first subtraction means, and an output connected to the output terminal.
7 more elements
A direct conversion receiver comprising:
- an input for receiving a signal modulated with a non-constant envelope;
- at least one mixer connected to the input for transposing the signal to a baseband signal;
- at least one compensation module connected to said at least one mixer for compensating the baseband signal for a DC voltage offset;
- and
- at least one amplifier connected to said at least one compensation module for amplifying the compensated baseband signal;
- wherein said at least one compensation module comprises
- an input terminal and an output terminal,
- a first envelope detector circuit connected to the input terminal for determining an envelope of an AC component of the baseband signal,
- a second envelope detector circuit connected to the input terminal for determining an envelope of the baseband signal,
- a first subtraction circuit having a first input connected to an output of said first envelope detector circuit, and a second input connected to an output of said second envelope detector circuit, and
- a second subtraction circuit having a first input connected to the input terminal, a second input connected to an output of said first subtraction circuit, and an output connected to the output terminal.
8 more elements
A mobile terminal comprising;
- an input for receiving a signal modulated with a non-constant envelope;
- an analog stage connected to the input and comprising
- at least one mixer for transposing the signal to a baseband signal;
- at least one compensation module connected to said at least one mixer for compensating the baseband signal for a DC voltage offset, and
- at least one amplifier connected to said at least one compensation module for amplifying the compensated baseband signal;
- and
- a digital stage connected to said analog stage for processing the compensated baseband signal;
- wherein said at least one compensation module comprises
- an input terminal and an output terminal,
- a first envelope detector circuit connected to the input terminal for determining an envelope of an AC component of the baseband signal,
- a second envelope detector circuit connected to the input terminal for determining an envelope of the baseband signal,
- a first subtraction circuit having a first input connected to an output of said first envelope detector circuit, and a second input connected to an output of said second envelope detector circuit, and
- a second subtraction circuit having a first input connected to the input terminal, a second input connected to an output of said first subtraction circuit, and an output forming the output terminal.
10 more elements
A method for processing a signal in a direct-conversion receiver, the method comprising:
- receiving the signal after having been modulated with a non-constant envelope;
- transposing the signal to a baseband signal;
- generating a compensation signal representative of a DC voltage offset within the direct-conversion receiver;
- and
- subtracting the compensation signal from the baseband signal;
- wherein generating the compensation signal comprises
- determining an envelope of an AC component of the baseband signal;
- determining an envelope of the baseband signal, and
- subtracting the envelope of the AC component of the baseband signal from the envelope of the baseband signal.
6 more elements
Dependencies are inferred from the claim text.