Characterization of the Near-Far problem in a CDMA-based acoustic localization system

In this work the Near-Far problem is characterized in the context of an acoustic local positioning system (ALPS). First, a simple energy normalization algorithm is presented to identify the Near-Far situation and also to resolve the signal detection in the case of non-overlapping receptions. Then, an improved signal interference cancellation (ISIC) algorithm is proposed to remove from the received signal most of the energy of the most powerful reception in case of overlapping receptions, thus allowing the detection of weaker signals. The performance of these algorithms has been first studied by simulating the behaviour of an ALPS with four beacons emitting BPSK-modulated Kasami codes installed in a rectangular anechoic chamber. The same study has been later conducted with signals acquired in a real scenario, using a third-generation iPad as the mobile node of the ALPS.

[1]  K. Arshak,et al.  A Model for Estimating the Real-Time Positions of a moving Object in Wireless Telemetry Applications using RF Sensors. , 2007, 2007 IEEE Sensors Applications Symposium.

[2]  Richard M. Lueptow,et al.  Theory for a gas composition sensor based on acoustic properties. , 2003, Measurement science & technology.

[3]  Juan R. Gonzalez,et al.  High-Precision Robust Broadband Ultrasonic Location and Orientation Estimation , 2009, IEEE Journal of Selected Topics in Signal Processing.

[4]  Abdelmoumen Norrdine,et al.  Adaptive Signal Processing for a Magnetic Indoor Positioning System , 2011 .

[5]  Álvaro Hernández,et al.  Advanced sensorial system for an acoustic LPS , 2007, Microprocess. Microsystems.

[6]  Andy Hopper,et al.  Implementing a Sentient Computing System , 2001, Computer.

[7]  Henk L. Muller,et al.  Low Cost Indoor Positioning System , 2001, UbiComp.

[8]  Santiago Mazuelas,et al.  Hybrid RSS-RTT Localization Scheme for Indoor Wireless Networks , 2010, EURASIP J. Adv. Signal Process..

[9]  Jesus Urena,et al.  Doppler-tolerant receiver for an ultrasonic LPS based on Kasami sequences , 2013 .

[10]  J. Werb,et al.  Designing a positioning system for finding things and people indoors , 1998 .

[11]  Volker Willert,et al.  Accuracy Evaluation for Automated Optical Indoor Positioning Using a Camera Phone , 2012 .

[12]  Sebastian Tilch,et al.  Current investigations at the ETH Zurich in optical indoor positioning , 2010, 2010 7th Workshop on Positioning, Navigation and Communication.

[13]  Álvaro Hernández,et al.  Efficient hardware implementation for detecting CSS-based Loosely Synchronous codes in a Local Positioning System , 2009, 2009 IEEE Conference on Emerging Technologies & Factory Automation.

[14]  Jack M. Holtzman,et al.  Analysis of a simple successive interference cancellation scheme in a DS/CDMA system , 1994, IEEE J. Sel. Areas Commun..

[15]  Américo Correia,et al.  Parallel interference cancellation with commutation signaling , 2000, 2000 IEEE International Conference on Communications. ICC 2000. Global Convergence Through Communications. Conference Record.

[16]  Mike Hazas,et al.  A high performance privacy-oriented location system , 2003, Proceedings of the First IEEE International Conference on Pervasive Computing and Communications, 2003. (PerCom 2003)..

[17]  David E. Culler,et al.  A practical evaluation of radio signal strength for ranging-based localization , 2007, MOCO.

[18]  Ig-Jae Kim,et al.  Indoor location sensing using geo-magnetism , 2011, MobiSys '11.

[19]  Mike Hazas,et al.  A Novel Broadband Ultrasonic Location System , 2002, UbiComp.

[20]  Steven Kay,et al.  Fundamentals Of Statistical Signal Processing , 2001 .

[21]  Fernando Seco Granja,et al.  Compensation of Multiple Access Interference Effects in CDMA-Based Acoustic Positioning Systems , 2014, IEEE Transactions on Instrumentation and Measurement.

[22]  S. Kay.  Fundamentals of statistical signal processing: estimation theory , 1993 .

[23]  Santiago Mazuelas,et al.  Robust Indoor Positioning Provided by Real-Time RSSI Values in Unmodified WLAN Networks , 2009, IEEE Journal of Selected Topics in Signal Processing.