A configurable acquisition engine for direct sequence (DS) spread spectrum (SS) is provided that is reconfigurable without increasing memory size for several use cases having different time-frequency uncertainties. The acquisition engine utilizes a frequency-domain decimation filter to reduce the number of output frequency points while still utilizing information from all frequency bins.

A configurable acquisition engine for direct sequence (DS) spread spectrum (SS) is provided that is reconfigurable without increasing memory size for several use cases having different time-frequency uncertainties. The acquisition engine utilizes a frequency-domain decimation filter to reduce the number of output frequency points while still utilizing information from all frequency bins.

In one implementation, a receiver has a module to calculate the cross-correlation between a portion of a digital representation of a received signal and a reference signal. The receiver also has a module to generate an estimate of a portion of a message potentially included in the digital representation of the received signal and a screening module to determine the likelihood that the received signal includes a message. For a received signal that is determined likely to include a message, the receiver includes a carrier refinement module to shift the frequency of carrier pulses in the digital representation of the received signal toward a desired frequency and to align the phase of carrier pulses in the digital representation of the received signal with a desired phase and a coherent matched filter to recover the message from the digital representation of the received signal.

Disclosed is a filter bank module having a substrate, an antenna port terminal, and a filter bank die. The filter bank die is fixed to the substrate and includes a first acoustic wave (AW) filter having a first antenna terminal coupled to the antenna port terminal and a first filter terminal, and a second AW filter having a second filter terminal, and a second antenna terminal coupled to the first antenna terminal to effectively diplex signals that pass through the first AW filter and the second AW filter.

Disclosed is a filter bank module having a substrate, an antenna port terminal, and a filter bank die. The filter bank die is fixed to the substrate and includes a first acoustic wave (AW) filter having a first antenna terminal coupled to the antenna port terminal and a first filter terminal, and a second AW filter having a second filter terminal, and a second antenna terminal coupled to the first antenna terminal to effectively diplex signals that pass through the first AW filter and the second AW filter.

A method for estimating a time of arrival of a signal transmitted over a wireless channel, includes receiving the signal by a receiving device; correlating the received signal with a filtered code sequence to create a correlation output, identifying in the correlation output, an observation window associated with a main lobe in the correlation output; and processing the observation window to determine a time of arrival of a first path component in the received signal. The filtered code sequence is formed by incorporating a time of arrival matched filter (TOA-MF) inside predetermined shaped code sequence. The TOA-MF is matched to the predetermined shaped code sequence and is based upon a power delay profile of the wireless channel. The predetermined shaped code sequence is a convolution of a predetermined shaping sequence and a predetermined code sequence.

A method for estimating a time of arrival of a signal transmitted over a wireless channel, includes receiving the signal by a receiving device; correlating the received signal with a filtered code sequence to create a correlation output, identifying in the correlation output, an observation window associated with a main lobe in the correlation output; and processing the observation window to determine a time of arrival of a first path component in the received signal. The filtered code sequence is formed by incorporating a time of arrival matched filter (TOA-MF) inside predetermined shaped code sequence. The TOA-MF is matched to the predetermined shaped code sequence and is based upon a power delay profile of the wireless channel. The predetermined shaped code sequence is a convolution of a predetermined shaping sequence and a predetermined code sequence.

A method for estimating a time of arrival of a signal transmitted over a wireless channel, includes receiving the signal by a receiving device to produce a received signal; filtering by a filter either the received signal or a code sequence, wherein the filter is designed to produce a correlation output that is near causal; correlating the received signal with the code sequence to create the correlation output that is near causal; wherein near causal means that early side lobes and an early part of a main lobe of the correlation output are sufficiently suppressed in order to substantially reduce an impact of delayed multipath onto a first path component in the received signal, wherein the first path is in an operating region; identifying in the correlation output, an observation window associated with a main lobe in the correlation output; processing the observation window to determine a time of arrival of the first path component in the received signal.

A method and an apparatus are provided for improving a carrier to noise density ratio (CNO) of a matched filter. A signal is received at a signal register of the matched filter. A local code is received at a local code register and a nulling register of the matched filter. An adder tree of the matched filter correlates the signal register and the local code register with respect to the nulling register to obtain a correlation result. The nulling register prevents high frequency samples of the signal register from affecting the correlation result.

A method and an apparatus are provided for improving a carrier to noise density ratio (CNO) of a matched filter. A signal is received at a signal register of the matched filter. A local code is received at a local code register and a nulling register of the matched filter. An adder tree of the matched filter correlates the signal register and the local code register with respect to the nulling register to obtain a correlation result. The nulling register prevents high frequency samples of the signal register from affecting the correlation result.