Receiver for bandspread signals, particularly GPS receiver

US5016257A · kind A · utility

Assignee

• Standard Elektrik Lorenz AG · DE

Inventors

• Michael Wolf · Mundelsheim, DE
• Wolfgang Beier · Weil der Stadt, DE

Key dates

• Filing date: Mar 13, 1989
• Grant date: May 14, 1991
• Expiry date: Mar 13, 2009

Classification

• Technology area (CPC G): Physics
• CPC primary: G01S19/30
• WIPO field: Measurement
• WIPO sector: Instruments

Abstract

Receivers for bandspread signals have a carrier PLL (20) for the carrier frequency and phase and a code PLL (20, 30 . . . 34) for the code frequency and phase. To be able to receive even very noisy signals, the carrier PLL, in particular, must have a very narrow bandwidth. This results in a very narrow capture range. According to the invention, instead of employing a complicated search strategy, advantage is taken of the fact that the code PLL locks in more easily. A signal is taken from the code PLL which indicates the difference between the desired value and the actual value of the code frequency. This signal is fed as an additional control signal to the carrier PLL.