The Chinese BeiDou system (BDS), having different types of satellites, is an important addition to the ever growing system of Global Navigation Satellite Systems (GNSS). It consists of Geostationary Earth Orbit (GEO) satellites, Inclined Geosynchronous Satellite Orbit (IGSO) satellites and Medium Earth Orbit (MEO) satellites. This paper investigates the receiver-dependent bias between these sat...

The paper proposes a maximum likelihood sequence estimator (MLSE) receiver for satellite communications. The satellite channel model is composed of a nonlinear traveling wave tube (TWT) amplifier followed by a multipath propagation channel. The receiver is composed of a neural network channel estimator (NNCE) and a Viterbi detector. The natural gradient (NG) descent is used for training. Comput...

Wireless transmitters deployed throughout an indoor environment offer the opportunity for accurate location tracking of mobile users. Using radio signal information alone, it is possible to determine the location of a roaming node at close to meter-level accuracy. We are particularly concerned with applications in which the robustness of the locationtracking infrastructure is at stake. For exam...

The vulnerability of civil GPS receiver to interference may be intentional or unintentional. Among all types of interference, replay attack intended as the most dangerous intentional one. The signal structure of replay attack is almost the same with the satellite signal. The interference effects can be reduce with the design of an appropriate filter in the receiver. This paper presents two meth...

The performance of many electronic systems is often limited by the performance of the clocks they use. For example, a receiver in the Global Positioning System (GPS) works by attempting to align an internally generated pseudorandom signal to an identical signal sent by a satellite and measuring the phase difference between the two. The receiver then calculates the time required for the satellit...

We investigate the role of ampli ed spontaneous emission (ASE) produced by an optical booster ampli er at the transmitter of free-space optical communication links. In a communication terminal with a single telescope for both transmission and reception, this ASE power has to be taken into account in connection with transmit-to-receive channel isolation, especially since it partly occupies the s...

The Location-based service on Wireless Sensor Networks, mainly depend on the Receiver Signal Strength (RSS) to measure the distance between the sender and receiver. The location unaware sensor nodes send beacon periodically which captured by anchor sensor nodes. However, the estimated distances may incur large error, and will risk the localization precision. A secant location estimation algorit...

This paper describes an innovative receiver architecture for the satellite-based automatic identification system. The receiver performance has been fully validated in the presence of the typical satellite channel characteristics. In particular, it is shown that the devised receiver provides an excellent performance against the noise, as well as a large resilience against message collisions, Dop...