Binary offset carrier modulation

Abstract: Current signaling for GPS employs phase shift keying (PSK) modulation using conventional rectangular (non-return to zero) spreading symbols. Attention has been focused primarily on the design of the spreading code and selection of the keying rates. But better modulation designs are available for next-generation radionavigation systems, offering improved performance and the opportunity for spectrum sharing while retaining implementation simplicity. This paper describes a class of particularly attractive modulations called binary offset carrier (BOC). It presents important characteristics of modulations for radionavigation, introduces several specific BOC designs that satisfy different applications in evolving radionavigation systems, describes receiver processing for these modulations, and provides analytical and numerical results that describe the modulations' performance and demonstrate advantages over comparable conventional PSK modulations with rectangular spreading symbols.

Abstract: This article presents a new tracking technique for sine-BOC(n,n) (or Manchester encoded) ranging signals, which is most likely to be a part of the new European Global Navigation Satellite System (GNSS), Galileo, signal plan. When traditional sine-BOC(n,n) tracking is considered, although offering excellent performance compared with current signals, it has the main drawback of potentially giving biased measurements. The new method presented herein allows the removal of this threat while maintaining the same level of performance. An adapted version of this technique can also be used for acquisition purposes

Abstract: A communication system by code modulation is described which incorporates an integration process in the original delta modulation system and is named delta-sigma modulation after its modulation mechanism. It has an advantage over delta modulation in dc level transmission and stability of performance, although both require essentially an equal bandwidth and complexity of circuitry. An experimental telemetering system employing delta-sigma modulation is also described.

Abstract: A split-spectrum military signal seems a likely candidate for future incorporation into L1 and/or L2. These split signal modulations, often referred to as “Offset Carrier” waveforms, present a technical challenge to the code tracking capability of the receiver. This paper describes a novel algorithm, which can be used by a receiver to track the offset carrier signal. The purpose of the algorithm is to resolve the ambiguity that arises due to the multipeaked autocorrelation function of the new signal, thus reducing false-lock probability. The algorithm is defined, some aspects of its performance are discussed, and simulation results are given.