摘要:
An apparatus for detecting an OFDM symbol encoded with a transmitted sequence including a filter having coefficients based on a simplified version of the transmitted sequence is disclosed. A computer program product having code and a wireless communications apparatus for performing the method are also described herein.
摘要:
A method for performing symbol timing estimation is disclosed herein. In one approach, the method includes defining a search space in a plurality of estimated magnitudes of channel taps; defining a search window in the search space; and locating a symbol timing estimate index in the search space corresponding to a maximum value of an energy of the plurality of estimated magnitudes of channel taps within the search window. A computer program product having code and a wireless communications apparatus for performing the method are also described herein.
摘要:
A method for performing carrier frequency offset estimation and frame synchronization is disclosed herein. In one approach, the method includes performing a first level frequency discrimination on at least one estimated channel tap to generate a frequency discriminated value; estimating a phase error from the frequency discriminated value; and, determining a predetermined frame synchronization pattern from the estimated phase error. A computer program product having code and a wireless communications apparatus for performing the method are also described herein.
摘要:
In embodiments, an adaptive tone erasure technique is applied to orthogonal frequency division multiplexing (OFDM) communications, such as ECMA-368 standard ultra-wideband (UWB) communications. A transmitter obtains jammed sub-carrier information and calculates an erasure mask. The jammed sub-carriers are nulled before transmitting to a receiver. In accordance with the erasure mask, bits falling on the jammed sub-carriers are replaced by erasure bits before interleaving, keeping the interleaver block size constant notwithstanding variations in the number of the jammed sub-carriers. The receiver also obtains the jammed sub-carrier information and the erasure mask. After the receiver deinterleaves the constant size blocks, it decodes the data without the erasure bits. The transmitter may detect the jammed sub-carriers itself, or obtain the information from the receiver. The receiver similarly may detect the jammed sub-carriers itself, or obtain the information from the transmitter.
摘要:
A method for performing symbol timing estimation is disclosed herein. In one approach, the method includes defining a search space in a plurality of estimated magnitudes of channel taps; defining a search window in the search space; and locating a symbol timing estimate index in the search space corresponding to a maximum value of an energy of the plurality of estimated magnitudes of channel taps within the search window. A computer program product having code and a wireless communications apparatus for performing the method are also described herein.
摘要:
A method for performing carrier frequency offset estimation and frame synchronization is disclosed herein. In one approach, the method includes performing a first level frequency discrimination on at least one estimated channel tap to generate a frequency discriminated value; estimating a phase error from the frequency discriminated value; and, determining a predetermined frame synchronization pattern from the estimated phase error. A computer program product having code and a wireless communications apparatus for performing the method are also described herein.
摘要:
In embodiments, an adaptive tone erasure technique is applied to orthogonal frequency division multiplexing (OFDM) communications, such as ECMA-368 standard ultra-wideband (UWB) communications. A transmitter obtains jammed sub-carrier information and calculates an erasure mask. The jammed sub-carriers are nulled before transmitting to a receiver. In accordance with the erasure mask, bits falling on the jammed sub-carriers are replaced by erasure bits before interleaving, keeping the interleaver block size constant notwithstanding variations in the number of the jammed sub-carriers. The receiver also obtains the jammed sub-carrier information and the erasure mask. After the receiver deinterleaves the constant size blocks, it decodes the data without the erasure bits. The transmitter may detect the jammed sub-carriers itself, or obtain the information from the receiver. The receiver similarly may detect the jammed sub-carriers itself, or obtain the information from the transmitter.
摘要:
An apparatus for detecting an OFDM symbol encoded with a transmitted sequence including a filter having coefficients based on a simplified version of the transmitted sequence is disclosed. A computer program product having code and a wireless communications apparatus for performing the method are also described herein.
摘要:
Methods, systems, and devices for supporting voice communications in a wireless communications system are provided. Some embodiments utilize multiple code channels to transmit the voice frames. These embodiments include parallel multi-code embodiments, offset multi-code embodiments, and multi-user multi-code embodiments. Some embodiments utilize flexible carrier bandwidths systems that may utilize portions of spectrum that may not be big enough to fit a normal bandwidth waveform. Some embodiments transmit and receive a subset of subframes of voice frames received over flexible bandwidth code channels. In some embodiments, a subset of subframes based on a flexible bandwidth scaling factor of one or more flexible bandwidth code channels is transmitted. The receiver may decode the voice frame based on the received subset of subframes. An outer loop power control set-point may be adjusted to provide a predetermined frame error rate based on the number of transmitted subframes.
摘要:
A method for Automatic Gain Control (AGC) in a receiver is performed by a circuit having an inner loop and an outer loop. The method includes performing an outer loop energy detection, mitigating interference using the outer loop energy detection, and performing a frequency domain energy measurement in the inner loop. The method also includes adjusting a digital gain component in the inner loop and an analog gain component in the outer loop in response to the frequency domain energy measurement.