ION GNSS 2011 : 24th International Technical Meeting of the Satellite Division of the Institute of Navigation 2011

This paper introduces the concept of Global Navigation Satellite System (GNSS) receiver design based on the principles derived from the cognitive radio (CR) technology. The receiver so designed is referred to as “cognitive GNSS receiver (CGR)”. The ontology and its rationale for CGR are described by defining different layers of cognition in GNSS receivers. The architecture of the cognition/decision module is presented, and the incremental differences with respect to existing receiver design methodologies are described. Two “use cases” are studied with cost (such as resource utilisation and power consumption) per fix and the usual GNSS performance parameters (such as the Time-to-First-Fix (TTFF), the acquisition/tracking sensitivity and the solution accuracy) as metrics, and the challenges in realising a full-fledged CGR are identified. It is shown that the CGR has the potential to replace the existing GNSS receiver architectures, especially in the multi-frequency and multi-system context

Proceedings of the 2011 International Technical Meeting of The Institute of Navigation January 24 - 26, 2011

This paper proposes a new modulation for a Global NavigationSatellite System (GNSS) to efficiently utilize a givenbandwidth. This modulation, referred to as Time-MultiplexedMulti-Carrier (TMMC), divides the available bandwidth intoN sub-bands such that each sub-band resembles a QuadraturePhase Shift Keying (QPSK) modulation and at the same timeallows the receiver to exploit the benefits of a widebandsignal. The generation of the new signal and its propertiesare described and the performance of TMMC is compared tothe other existing modulation schemes. The benefits of usingTMMC modulation for wideband signals in terms of overcomingthe errors due to propagation channel impairments,continuous wave (CW) interference mitigation and receiverdesign complexity is discussed

Proceedings of the 21st International Technical Meeting of the Satellite Division of The Institute of Navigation (ION GNSS 2008)

In GNSS, longer integrations are required to obtain better signal-to-noise ratio during the signal synchronization process. However the presence of secondary codes on the top of primary codes puts a constraint on the coherent integration duration for pilot channels in a similar way to the effect of data bits in data-carrying channels. In this paper we explore the problem of coherent integration over periods longer than one primary code length and the acquisition of secondary code chip position. We propose an acquisition engine architecture which can handle both these problems together