# Xiantao Sun

> Modem software engineer at Google

Location: Cupertino, California, United States
Profile: https://flows.cv/xiantao

I am passionate about LTE, LTE-Advanced, 802.11n, 802.11ac, and other future wireless technologies

## Work Experience
### Staff Software Engineer @ Google
Jan 2019 – Present | San Francisco Bay Area
Develop Pixel modem software

### Modem FW Engineer @ Apple
Jan 2012 – Jan 2019 | Cupertino, CA
L1 SW and firmware development for 3GPP
LTE-A signal processing algorithms and improvements

### Senior Engineer @ Qualcomm
Jan 2010 – Jan 2012 | San Diego
PHY firmware development for 3GPP TD-SCDMA:
*As a key member of TD-SCDMA FW team, designed and Implemented channel estimation, UE measurement, frequency tracking and time tracking algorithms for Qualcomm's first generation TD-SCDMA modem
*Brought up and supported commercialization of Qualcomm's first generation modem with TD-SCDMA support: MDM 9x15

### Intern @ Cisco Systems
Jan 2008 – Jan 2008
June 2007 - August 2007
June 2008 - August 2008
I spent two summers in research and development related to 802.11n in 2007 and 2008. During these two summers: 
*Created a complete 802.11n end to end simulation platform with advanced features like STBC, transmit beamforming. This simulator is widely used for advanced WiFi research and proof of concept studies by Cisco 

*Co-invented a channel estimation algorithm that enables implicit transmit beamforming and spatial multiplexing without assistance from 802.11n/ac clients equipped with multiple transmit antennas. This invention is an essential part of Cisco's ClientLink technology.  "ClientLink 3.0 uses its advanced, patent pending algorithms to provide full beamforming gain, whether clients help sound out the channel or not" [http://www.cisco.com/c/en/us/products/collateral/wireless/aironet-3700-series/white-paper-c11-731150.pdf]

### System Engineer @ Siemens Mobile Networks
Jan 2003 – Jan 2006
PHY SW development for 3GPP TD-SCDMA base station


## Education
### Ph.D. in Wireless Communications
University of Delaware

### Bsc/Msc in Electrical Engineering
Xidian University


## Contact & Social
- LinkedIn: https://linkedin.com/in/xiantao-sun-477a849

---
Source: https://flows.cv/xiantao
JSON Resume: https://flows.cv/xiantao/resume.json
Last updated: 2026-04-12