Rectangular room dimensions estimation using narrowband signal and sectorized antennas

A system for estimation of unknown rectangular room dimensions based on two radio transceivers, both capable of full duplex operations, is presented. The approach is based on CIR measurements taken at the same place where the signal is transmitted (generated), commonly known as self- to-self CIR. Another novelty is the receiver antenna design which consists of eight sectorized antennas with 45° aperture in the horizontal plane, whose total coverage corresponds to the isotropic one. The dimensions of a rectangular room are reconstructed directly from radio impulse responses by extracting the information regarding features like round trip time, received signal strength and reverberation time. Using radar approach the estimation of walls and corners positions are derived. Additionally, the analysis of the absorption coefficient of the test environment is conducted and a typical coefficient for office room with furniture is proposed. Its accuracy is confirmed through the results of volume estimation. Tests using measured data were performed, and the simulation results confirm the feasibility of the approach

Self-positioning and mapping of rectangular rooms with sectorized narrowband antennas

A system for simultaneous 2D estimation of rectangular room and transceiver localization is proposed. The system is based on two radio transceivers, both capable of full duplex operations (simultaneous transmission and reception). This property enables measurements of channel impulse response (CIR) at the same place the signal is transmitted (generated), commonly known as self-to-self CIR. Another novelty of the proposed system is the spatial CIR discrimination that is possible with the receiver antenna design which consists of eight sectorized antennas with 45° aperture in the horizontal plane and total coverage equal to the isotropic one. The dimensions of a rectangular room are reconstructed directly from spatial radio impulse responses by extracting the information regarding round trip time (RTT). Using radar approach estimation of walls and corners positions is derived. Tests using measured data were performed, and the simulation results confirm the feasibility of the approach

RF- Front-End Non-Linear coupling cancellation = Cancelación de acoplo no lineal en frontales de RF

Abstract In order to extend the communication range, improve reliability and achieve higher bit rates recent trends in communication industry include the use of multiple antennas in transmitter and at the receiver. At the same time the dimensions of mobile terminals are getting smaller incrementing the level of electronic interferences in their interior. The closeness of data metallic wires and many electronic circuits creates rather hostile environment which, among other dis¬tortions, stimulates the appearance of undesirable energy transfers between physical mediums. This signal distortion, also known as multiantenna radio-frequency (RF) front-end coupling is analyzed throughout the thesis, and as a result three coupling cancellation procedures are developped and later tested in simulated coupling environments. The coupling phenomena depends on many variables, starting with the selection of electronic elements and RF front-end design, up to the transmission system working conditions. Since the complexity of coupling distortion discards simple linear models, nonlinear modelling based on polynomials, limited to third order, is implemented. The coupling model proposed in this thesis is consistent with the analog electronic elements and follows the nonlinear behaviour experienced in many RF front end imperfections. The coupling cancellation approach is based on nonlinear software decoupling module located at the output of analog-to-digital (AD) converter. The advantage of this location is that it deals directly with sampled physical data avoiding any dependency on specific signal type. Hence the decoupling module can be easily implemented in wide range of transmission systems. Inside the module, signal enhancement is achieved with the approximation of inverse nonlinear coupling function based on the sum of two independent polynomials modelling the inverse function of coupling between two antennas. The adequate decoupling surface is obtained with three different search methods: Simulated Annealing (SA), Improved Fast Simulated Annealing (IFSA) and Guided Multi-Level (GML) search. The thesis is divided into eight chapters. The first two correspond to technological back¬ground and RF front end description, respectively. In chapter three, nonlinear coupling model is developed with emphasis on receiver's RF front-end based on I/Q downconverter. Chapter four introduces the inverse coupling function and develops the adequate approximation surface model used for coupling cancellation. The three approaches used for the corresponding surface search are than analyzed in chapter five. The following two chapters first simplify the surface 3 form in noiseless conditions, and afterwords the performance of adopted search methods is an¬alyzed in environment with AWGN noise during the calibration. The last chapter corresponds to conclusion and possible future applications of decoupling module.

D2.2 Cooperative Positioning (Intermediate Report)

This deliverable presents preliminary results about novel cooperative positioning schemes and performance analysis from the communication aspects. The focus is on small scale indoor scenarios with impulse radio (IR) ultra wideband (UWB) complementing cellular communication systems, middle scale indoor scenario with WiFi and ZigBee systems, and large scale outdoor such as cellular communication systems. The proposed cooperative positioning schemes include the static single-hop positioning scheme for WiFi, static multi-hop positioning using non parametric belief propagation (BP), generalized multiuser hybrid data fusion (HDF), joint peer-to-peer ranging and distributed positioning. The overhead/performance trade-off is carefully investigated for distributed positioning schemes. Moreover, physical-level performance, mainly Cramer-Rao lower bound (CRLB), is analyzed for a new cooperative positioning model