Dynamic cancellation of passive intermodulation interference

US9026064B2 · kind B2 · utility

Assignee

• Telefonaktiebolaget LM Ericsson (Publ) · SE

Inventors

• Meng Wang · Sundbyberg, SE
• Shaohua Li · Beijing, CN
• Robert Baldemair · Solna, SE
• Jung-Fu Cheng · Fremont, US
• Farshid Ghasemzadeh · Sollentuna, SE
• Magnus Larsson · Sollentuna, SE
• Johan Sköld · Solna, SE

Key dates

• Filing date: Sep 9, 2011
• Grant date: May 5, 2015
• Expiry date: Feb 8, 2032

Classification

• Technology area (CPC H): Electricity
• CPC primary: H04B1/525
• WIPO field: Telecommunications
• WIPO sector: Electrical engineering

Abstract

A wireless communication node (10) dynamically estimates passive intermodulation (PIM) interference coupled into the node's receive path from the transmission of a composite signal through the node's transmit path. The node (10) then cancels the estimated PIM interference in the receive path. In some embodiments, the node dynamically estimates the PIM interference as a function of the composite signal that models PIM interference generation and coupling in the node (10) according to one or more coefficients (30). The coefficients (30) may be determined by transmitting a test signal (34) during a test stage, when the node (10) is not scheduled to receive any signal. Later, when the composite signal (18) is transmitted, the node (10) uses the coefficients (10) to dynamically estimate and cancel the resulting PIM interference.