公开(公告)号：US12213092B2

公开(公告)日：2025-01-28

申请号：US17494335

申请日：2021-10-05

Applicant: Parallel Wireless, Inc.

Inventor： Hemanth Palally ,  Saikat Senapati ,  Somasekhar Pemmasani

IPC: H04W56/00 ,  H04L27/26 ,  H04W74/0833

Abstract: Systems, methods and computer software are disclosed for providing high resolution timing advance estimation based on Physical Random Access Channel (PRACH). An example method includes receiving a preamble signal r(n) having a predetermined sampling frequency and a predetermined length; correlating a down sampled version of the received preamble with a reference preamble sequence c(n) using an FFT method to provide correlation output Ryc; using a peak value P of the correlation output Ryc to detect a preamble ID and a timing advance at a resolution of 24Ts; zero padding sequences Y(k) and C(k) so that they have a predetermined length resulting in sequences Y_hat(k) and C_hat(k), which are 1024-point FFT of y(n) and c(n); performing a maximum likelihood estimation (MLE) to estimate a timing offset; and detecting a peak value out of the R_hat(m) and using a corresponding index Q to provide a timing advance with an accuracy of 2Ts.

公开(公告)号：US20220030535A1

公开(公告)日：2022-01-27

申请号：US17494335

申请日：2021-10-05

Applicant: Parallel Wireless, Inc.

Inventor： Hemanth Palally ,  Saikat Senapati ,  Somasekhar Pemmasani

IPC: H04W56/00 ,  H04L27/26 ,  H04W74/08

Abstract: Systems, methods and computer software are disclosed for providing high resolution timing advance estimation based on Physical Random Access Channel (PRACH). An example method includes receiving a preamble signal r(n) having a predetermined sampling frequency and a predetermined length; correlating a down sampled version of the received preamble with a reference preamble sequence c(n) using an FFT method to provide correlation output Ryc; using a peak value P of the correlation output Ryc to detect a preamble ID and a timing advance at a resolution of 24 Ts; zero padding sequences Y(k) and C(k) so that they have a predetermined length resulting in sequences Y_hat(k) and C_hat(k), which are 1024-point FFT of y(n) and c(n); performing a maximum likelihood estimation (MLE) to estimate a timing offset; and detecting a peak value out of the R_hat(m) and using a corresponding index Q to provide a timing advance with an accuracy of 2 Ts.

公开(公告)号：US20200099565A1

公开(公告)日：2020-03-26

申请号：US16582811

申请日：2019-09-25

Applicant: Parallel Wireless, Inc.

Inventor： Hemanth Palally ,  Saikat Senapati ,  Somasekhar Pemmasani ,  Ramesh Annavajjala

IPC: H04L27/26 ,  H04W64/00

Abstract: Systems, methods and computer software are disclosed for providing high resolution timing advance estimation based on Physical Random Access Channel (PRACH). An example method includes receiving a preamble signal r(n); performing signal conditioning on r(n); down sampling the signal and performing antialiasing filtering to provide a y(n) signal; correlating y(n) with a reference preamble with a reference preamble sequence c(n) to provide correlation output Ryc; using a peak value P of the correlation output Ryc to detect a preamble ID and a timing advance; constructing a sequence s(n) by segmenting r_centered(n) for length L around an index P*24; performing time domain interpolation of c(n) around index P to obtain a sequence c_interpolated(n); performing time domain interpolation between sequences s(n) and c_interpolated(n); detecting a peak position Q of the correlation; and deriving TA as P*24−L/2+q in terms of Ts.

公开(公告)号：US11102044B2

公开(公告)日：2021-08-24

申请号：US16582811

申请日：2019-09-25

Applicant: Parallel Wireless, Inc.

Inventor： Hemanth Palally ,  Saikat Senapati ,  Somasekhar Pemmasani ,  Ramesh Annavajjala

IPC: H04L27/26 ,  H04W64/00 ,  G01S13/76

Abstract: Systems, methods and computer software are disclosed for providing high resolution timing advance estimation based on Physical Random Access Channel (PRACH). An example method includes receiving a preamble signal r(n); performing signal conditioning on r(n); down sampling the signal and performing antialiasing filtering to provide a y(n) signal; correlating y(n) with a reference preamble with a reference preamble sequence c(n) to provide correlation output Ryc; using a peak value P of the correlation output Ryc to detect a preamble ID and a timing advance; constructing a sequence s(n) by segmenting r_centered(n) for length L around an index P*24; performing time domain interpolation of c(n) around index P to obtain a sequence c_interpolated(n); performing time domain interpolation between sequences s(n) and c_interpolated(n); detecting a peak position Q of the correlation; and deriving TA as P*24−L/2+q in terms of Ts.

公开(公告)号：US11140647B2

公开(公告)日：2021-10-05

申请号：US16576369

申请日：2019-09-19

Applicant: Parallel Wireless, Inc.

Inventor： Hemanth Palally ,  Saikat Senapati ,  Somasekhar Pemmasani

IPC: H04W4/00 ,  H04W56/00 ,  H04L27/26 ,  H04W74/08

Abstract: Systems, methods and computer software are disclosed for providing high resolution timing advance estimation based on Physical Random Access Channel (PRACH). An example method includes receiving a preamble signal r(n) having a predetermined sampling frequency and a predetermined length; correlating a down sampled version of the received preamble with a reference preamble sequence c(n) using an FFT method to provide correlation output Ryc; using a peak value P of the correlation output Ryc to detect a preamble ID and a timing advance at a resolution of 24Ts; zero padding sequences Y(k) and C(k) so that they have a predetermined length resulting in sequences Y_hat(k) and C_hat(k), which are 1024-point FFT of y(n) and c(n); performing a maximum likelihood estimation (MLE) to estimate a timing offset; and detecting a peak value out of the R_hat(m) and using a corresponding index Q to provide a timing advance with an accuracy of 2Ts.

公开(公告)号：US20200092835A1

公开(公告)日：2020-03-19

申请号：US16576369

申请日：2019-09-19

Applicant: Parallel Wireless, Inc.

Inventor： Hemanth Palally ,  Saikat Senapati ,  Somasekhar Pemmasani

IPC: H04W56/00 ,  H04W74/08 ,  H04L27/26

Abstract: Systems, methods and computer software are disclosed for providing high resolution timing advance estimation based on Physical Random Access Channel (PRACH). An example method includes receiving a preamble signal r(n) having a predetermined sampling frequency and a predetermined length; correlating a down sampled version of the received preamble with a reference preamble sequence c(n) using an FFT method to provide correlation output Ryc; using a peak value P of the correlation output Ryc to detect a preamble ID and a timing advance at a resolution of 24Ts; zero padding sequences Y(k) and C(k) so that they have a predetermined length resulting in sequences Y_hat(k) and C_hat(k), which are 1024-point FFT of y(n) and c(n); performing a maximum likelihood estimation (MLE) to estimate a timing offset; and detecting a peak value out of the R_hat(m) and using a corresponding index Q to provide a timing advance with an accuracy of 2Ts.