Automatic Dependent Surveillance, Surveillance–Broadcast, secondary surveillance radars, and Mode S are key air technologies representing a critical component of next-generation transportation systems. However, compared to 1090-MHz demodulators decoders, which have plenty implementations, the 1030-MHz uplink receivers are, in general, scarcely, if at all, represented. In this article, we presen...

Effective demodulation of amplitude and phase is a requirement in wide array applications. Recent efforts have increased the performance, particular, Lyapunov demodulator allows bandwidths up to carrier frequency signal. However, being inherently restricted first-order filtering input signal, it highly sensitive components outside its passband region. This makes unsuitable for certain applicati...

This paper presents a novel iterative algorithm for demodulation and turbo decoding. Using this algorithm, short coded messages, which can be independently processed on a distributed computer, can achieve an improved bit-error rate for a small increase in computational load. We also present a trade study of the effects of message length, memory order, signal to noise ratio, and iterations in ou...

This paper considers practically relevant aspects and advantages of pulse-shaping orthogonal/biorthogonal frequency division multiplexing (OFDM/BFDM) systems. We analyze the intersymbol/intercarrier interference (ISI/ICI) in such systems when they operate over time-varying channels. Two methods for an ISI/ICI-minimizing pulse design are proposed, and efficient FFT-based modulator and demodulato...

This paper describes the Customizable Coherent Demodulation Algorithm, a servo demodulator which provides dramatically improved performance over the currently used servo demodulation methods for disk drives. The demodulation algorithm proposed here makes better use of knowledge about the readback signal coming from the disk to provide better noise immunity and more immunity to other nonidealiti...

Abstract—A direct 61GHz demodulator, based on a rectangular waveguide (WR-12) six-port, is presented in this letter. The six-port device, composed of four 90◦ hybrid couplers fabricated in a metal block of brass, is implemented in ADS software. Good agreement between QPSK demodulation results using an ideal six-port model and a second one, based on the S-parameter measurements of a 61GHz hybrid...