US 9,813,108 B2  
Method of generating binary offset carrier correlation function based on partial correlation functions, apparatus for tracking binary offset carrier signal, and spread spectrum signal receiver system using the same  
Keun Hong Chae, Suwonsi (KR); and Seok Ho Yoon, Suwonsi (KR)  
Assigned to Research & Business Foundation Sungkyunkwan University, Suwonsi (KR)  
Filed by RESEARCH & BUSINESS FOUNDATION SUNGKYUNKWAN UNIVERSITY, Suwonsi (KR)  
Filed on May 20, 2016, as Appl. No. 15/160,187.  
Application 15/160,187 is a division of application No. 14/525,937, filed on Oct. 28, 2014, abandoned.  
Claims priority of application No. 1020130129223 (KR), filed on Oct. 29, 2013.  
Prior Publication US 2016/0269073 A1, Sep. 15, 2016  
This patent is subject to a terminal disclaimer.  
Int. Cl. H04B 1/707 (2011.01); H04B 1/7085 (2011.01); H04B 1/7075 (2011.01); G01S 19/30 (2010.01) 
CPC H04B 1/7085 (2013.01) [G01S 19/30 (2013.01); H04B 1/70752 (2013.01); H04B 2001/70706 (2013.01); H04B 2201/707 (2013.01)]  20 Claims 
1. A delay lock loop (DLL) to track a code delay phase value for a local code to be correlated with a received BOCmodulated
signal in which N pulses successively occur in a single period T_{c }of a spreading code chip in a spread spectrum signal receiver system, the DLL comprising:
a processor configured to:
generate an early and late delayed received signal pair B(t+τ+Δ/2) and B(t+τ−Δ/2), based on phase delay τ and a delay value
difference Δ, with respect to a received signal pulse train of a received signal B(t), wherein the B(t+τ+Δ/2) is an early
signal and the B(t+τ−Δ/2) is a late signal,
generate N early partial correlation functions S_{m}(τ+Δ/2) (where 0≤m≤N−1) and N late partial correlation functions S_{m}(τ−Δ/2) by performing an autocorrelation operation on the early and late delayed received signal pair B(t+τ+Δ/2) and B(t+τ−Δ/2)
with respect to a total time T(0≤t≤T),
obtain an early intermediate correlation function R_{0}(τ+Δ/2;a) by performing an elimination operation on an early subcorrelation function pair T_{1}(τ+Δ/2;a) and T_{2}(τ+Δ/2;a) obtained by combining first and last early partial correlation functions S_{0}(τ+Δ/2) and S_{N1}(τ+Δ/2) based on a main peak shape parameter a such that only a main peak is left, and generate an early main correlation
function R_{proposed}(τ+Δ/2;a) by superposing results obtained by additionally performing an elimination operation on the early intermediate correlation
function R_{0}(τ+Δ/2;a) and each of the early partial correlation functions S_{m}(τ+Δ/2),
obtain a late intermediate correlation function R_{0}(τ−Δ/2;a) by performing an elimination operation on a late subcorrelation function pair T_{1}(τ−Δ/2;a) and T_{2}(τ−Δ/2;a) obtained by combining first and last late partial correlation functions S_{0}(τ−Δ/2) and S_{N1}(τ−Δ/2) based on a main peak shape parameter a, such that only a main peak is left, and generate a late main correlation function
R_{proposed}(τ−Δ/2;a) by superposing results obtained by additionally performing an elimination operation on the late intermediate correlation
function R_{0}(τ−Δ/2;a) and each of the late partial correlation functions S_{m}(τ−Δ/2), and
determine a phase delay τ for the received signal based on a discrimination output of a discrimination function based on values
of the early and late main correlation functions, and
output the determined phase delay τ,
wherein the elimination operation is related to an algebraic relation in which when real numbers x and y are xy≤0, x+y−x−y=0.
