Severity: Warning
Message: file_get_contents(https://...@gmail.com&api_key=61f08fa0b96a73de8c900d749fcb997acc09): Failed to open stream: HTTP request failed! HTTP/1.1 429 Too Many Requests
Filename: helpers/my_audit_helper.php
Line Number: 143
Backtrace:
File: /var/www/html/application/helpers/my_audit_helper.php
Line: 143
Function: file_get_contents
File: /var/www/html/application/helpers/my_audit_helper.php
Line: 209
Function: simplexml_load_file_from_url
File: /var/www/html/application/helpers/my_audit_helper.php
Line: 3098
Function: getPubMedXML
File: /var/www/html/application/controllers/Detail.php
Line: 574
Function: pubMedSearch_Global
File: /var/www/html/application/controllers/Detail.php
Line: 488
Function: pubMedGetRelatedKeyword
File: /var/www/html/index.php
Line: 316
Function: require_once
Severity: Warning
Message: Attempt to read property "Count" on bool
Filename: helpers/my_audit_helper.php
Line Number: 3100
Backtrace:
File: /var/www/html/application/helpers/my_audit_helper.php
Line: 3100
Function: _error_handler
File: /var/www/html/application/controllers/Detail.php
Line: 574
Function: pubMedSearch_Global
File: /var/www/html/application/controllers/Detail.php
Line: 488
Function: pubMedGetRelatedKeyword
File: /var/www/html/index.php
Line: 316
Function: require_once
Optical parameter estimation based on the data obtained by coherent optical receivers is critical for optical performance monitoring (OPM) and the stable operation of the receiver digital signal processing (DSP). A robust multi-parameter estimation is intricate due to the interference of various system effects. By resorting to the cyclostationary theory, we are able to formulate a chromatic dispersion (CD), frequency offset (FO), and optical signal-to-noise ratio (OSNR) joint estimation strategy that is resistant to the random polarization effect, including polarization mode dispersion (PMD) and polarization rotation. The method uses data directly after the DSP resampling and matched filtering. Both numerical simulation and field optical cable experiment validate our method.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1364/OE.489827 | DOI Listing |
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!