Dc removal techniques for wireless networking
AssigneeQUALCOMM Incorporated
InventorDaniel Filipovic
Life of this patent
Estimating the term…
Abstract
A wireless communication device (WCD) performs DC removal on a received signal using a coarse DC removal unit that removes relatively large DC components and a fine DC removal loop that removes residual DC components. The coarse DC removal unit can be implemented in a receiver, and the fine DC removal loop can be implemented in a modem. In addition, a coarse DC estimation loop implemented on the modem may be coupled to the coarse DC removal unit to update DC offset values stored in the DC removal unit. By storing coarse DC offset values locally on the receiver, DC removal can be achieved very quickly.
Claims29
A method comprising:
- estimating a DC offset value for a baseband signal associated with a first received packet;
- updating a memory of a receiver with the estimated DC offset value;
- and
- removing a DC offset from a baseband signal associated with a second received packet according to the estimated DC offset value stored in memory.
A method comprising:
- removing a DC offset from an analog baseband signal associated with a received packet according to an estimated digital DC offset value stored in memory;
- and
- removing a residual DC offset from a digital representation of the baseband signal using a residual DC removal loop.
A method comprising:
- storing a plurality of DC offset values corresponding to a number of different gain states;
- processing a received baseband signal associated with a packet according to a selected one of the plurality of gain states;
- and
- removing a DC offset from the received baseband signal according to a stored DC offset value corresponding to the selected gain state.
A wireless communication device comprising:
- a receiver including a memory that stores a digital representation of a coarse DC offset value, a DC digital to analog converter that converts the stored digital representation to an analog DC offset signal, and a difference amplifier that removes the analog DC offset signal from a received baseband signal associated with a packet;
- and
- a modem coupled to the receiver, wherein the modem converts the baseband signal to a digital baseband signal, estimates a residual DC offset associated with the digital baseband signal, and updates the stored digital DC offset value in the receiver.
A receiver comprising:
- a memory that stores a digital representation of a coarse DC offset value;
- a DC digital to analog converter that converts the stored digital representation to an analog DC offset signal;
- and
- a difference amplifier that removes the analog DC offset signal from a received baseband signal associated with a packet.
A modem comprising:
- a fine DC removal unit that removes a residual DC offset from digital representations of a baseband signal associated with a first packet;
- and
- a coarse DC estimator that estimates the residual DC offset and sends the estimate to a receiver for use in processing a second packet.
A wireless communication device comprising:
- a receiver that removes a DC offset from an analog baseband signal associated with a received packet according to an estimated digital DC offset value stored in memory;
- and
- a modem that removes a residual DC offset from a digital representation of the baseband signal using a residual DC removal loop.
A wireless communication device comprising:
- a receiver that stores a plurality of DC offset values for a number of different gain states, processes a received baseband signal associated with a packet according to a selected one of the plurality of gain states, and removes a DC offset from the received baseband signal according to a stored DC offset value associated with the selected gain state.
An apparatus comprising:
- means for estimating a DC offset value for a baseband signal associated with a first received packet;
- means for updating a memory of a receiver with the estimated DC offset value;
- and
- means for removing a DC offset from a baseband signal associated with a second received packet according to the estimated DC offset value stored in memory.
An apparatus comprising:
- means for removing a DC offset from an analog baseband signal associated with a received packet according to an estimated digital DC offset value stored in memory;
- and
- means for removing a residual DC offset from a digital representation of the baseband signal using a residual DC removal loop.
An apparatus comprising:
- means for storing a plurality of DC offset values for a number of different gain states;
- means for processing a received baseband signal associated with a packet according to a selected one of the plurality of gain states;
- and
- means for removing a DC offset from the received baseband signal according to a stored DC value associated with the selected gain state.
A method comprising:
- estimating a DC offset value for a baseband signal associated with a first received packet;
- and
- removing a DC offset from a baseband signal associated with a second received packet according to the estimated DC offset value.
Dependencies are inferred from the claim text.