Offset correction for a homodyne radio
First Claim
1. A homodyne receiver device with DC offset correction comprising:
- demodulating means for demodulating an RF signal to produce a baseband signal, said baseband signal having a DC offset;
a dynamic offset correction circuit adapted to receive said baseband signal and to determine thereform a dynamic DC offset of said baseband signal and applying a dynamic offset correction to said baseband signal;
timing means for acquiring a timing signal from said baseband signal for synchronization to a transmitter; and
a switchable high pass filter having a first predetermined frequency cutoff and a second predetermined frequency cutoff adapted to receive said baseband signal, wherein said switchable high pass filter is selectively switched between said first predetermined frequency cutoff before synchronization and said second predetermined frequency cutoff after synchronization.
5 Assignments
0 Petitions
Accused Products
Abstract
DC offset cancellation and timing recovery is provided in a homodyne receiver. The homodyne receiver demodulates an RF signal to produce a baseband signal. An initial offset correction module determines an initial DC offset of the baseband signal. An initial offset correction is applied to the baseband signal to provide an initial corrected baseband signal. Wherein, a dynamic DC offset correction module determines a dynamic DC offset. A dynamic DC offset correction is applied to the initial corrected baseband signal providing a dynamic corrected baseband signal. A timing signal is acquired from the baseband signal for synchronizing the receiver to a transmitter. A method for correcting DC offset of a baseband signal in a homodyne receiver is also described.
-
Citations
26 Claims
-
1. A homodyne receiver device with DC offset correction comprising:
-
demodulating means for demodulating an RF signal to produce a baseband signal, said baseband signal having a DC offset; a dynamic offset correction circuit adapted to receive said baseband signal and to determine thereform a dynamic DC offset of said baseband signal and applying a dynamic offset correction to said baseband signal; timing means for acquiring a timing signal from said baseband signal for synchronization to a transmitter; and a switchable high pass filter having a first predetermined frequency cutoff and a second predetermined frequency cutoff adapted to receive said baseband signal, wherein said switchable high pass filter is selectively switched between said first predetermined frequency cutoff before synchronization and said second predetermined frequency cutoff after synchronization. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10)
-
-
11. A homodyne receiver device with DC offset correction comprising:
-
demodulating means for demodulating an RF signal to produce a baseband signal, said baseband signal having a DC offset; and a dynamic offset correction circuit adapted to receive said baseband signal and to determine thereform a dynamic DC offset of said baseband signal and applying a dynamic offset correction to said baseband signal; wherein said dynamic offset correction circuit determines said dynamic DC offset after synchronization by storing a data frame and calculating an average potential value of a preamble of said data frame and a post amble of said data frame.
-
-
12. In a homodyne receiver having demodulating means for demodulating an RF signal to produce a baseband signal, a device for providing DC offset correction comprising;
-
initial offset correction circuit for determining an initial DC offset of said baseband signal and applying an initial offset correction to said baseband signal to provide an initial corrected baseband signal; dynamic offset correction circuit for determining a dynamic DC offset of said initial corrected baseband signal and applying a dynamic offset correction to said initial corrected baseband signal; timing means for acquiring a timing signal from said baseband signal for synchronization to a transmitter; and a switchable high pass filter having a first predetermined frequency cutoff and a second predetermined frequency cutoff adapted to receive said initial corrected baseband signal, wherein said switchable high pass filter is selectively switched between said first predetermined frequency cutoff before synchronization and said second predetermined frequency cutoff after synchronization. - View Dependent Claims (13, 14, 15, 16, 17, 18, 19)
-
-
20. In a homodyne receiver having demodulating means for demodulating an RF signal to produce a baseband signal, a device for providing DC offset correction comprising:
-
initial offset correction circuit for determining an initial DC offset of said baseband signal and applying an initial offset correction to said baseband signal to provide an initial corrected baseband signal; and dynamic offset correction circuit for determining a dynamic DC offset of said initial corrected baseband signal and applying a dynamic offset correction to said initial corrected baseband signal; wherein said dynamic offset correction circuit determines said dynamic DC offset after synchronization by storing a data frame and calculating an average potential value of a preamble of said data frame and a post amble of said data frame.
-
-
21. A method for correcting a baseband signal having a DC offset in a homodyne receiver, said method comprising the steps of:
-
determining a dynamic DC offset of said baseband signal; applying a dynamic offset correction to said baseband signal; acquiring a timing signal from said baseband signal for synchronization to a transmitter; and switching a high pass filter from a first predetermined frequency cutoff to a second predetermined frequency cutoff after acquiring said timing signal. - View Dependent Claims (22, 23, 24, 25)
-
-
26. A method for correcting a baseband signal having a DC offset in a homodyne receiver, said method comprising the steps of:
-
determining a dynamic DC offset of said baseband signal; and applying a dynamic offset correction to said baseband signal; wherein the step of determining a dynamic DC offset comprises storing a data frame and calculating an average potential value of a preamble of said data frame and a post amble of said data frame.
-
Specification