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Digital Modulation Techniques for Software Defined Radio Applications
Published in Rajeshree Raut, Ranjit Sawant, Shriraghavan Madbushi, Cognitive Radio, 2020
Rajeshree Raut, Ranjit Sawant, Shriraghavan Madbushi
In binary phase shift keying (BPSK), the phase of a constant amplitude carrier is switched between two values according to the two possible signals m1 and m2 corresponding to binary 1 and 0, respectively.
Communications, Signal Processing, and Data Handling
Published in Douglas O. J. deSá, Instrumentation Fundamentals for Process Control, 2019
A more common type of modulation is phase-shift keying (PSK), in which the data signal changes the phase of the carrier by 0 or n radians (180°) corresponding to 0 or 1, and comparison against a reference carrier at the receiver decodes and reconstitutes the absolute values directly. In practice, the system is very susceptible to interference, leading to phase ambiguity (spurious phase generation); hence, a modified PSK is used. In this system each data element has a phase change corresponding to that of the preceding element; decoding is made possible by determining the relative phase changes. This method increases the noise immunity significantly and is called differential phase-shift keying (DPSK).
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Published in Mário Marques da Silva, Cable and Wireless Networks, 2018
The phase shift keying (PSK) is an elementary modulation scheme that uses the phase of a carrier as the parameter to encode bits. As shown in Figure 6.20, logic state 1 is represented by the transmission of a carrier wave with the phase 0 and logic state 0 is represented by the transmission of a carrier wave with the phase π. Alternatively, the encoded logic states can be reversed.
Oversampled CI-OFDM Baseband Transceiver Architecture and Its FPGA Prototype
Published in IETE Journal of Research, 2022
Rakesh Palisetty, Kailash Chandra Ray
In [4–7], CI-OFDM scheme is shown as an efficient method to reduce the PAPR without degrading the BER performance and an advantage of resistance against deep fades. Also, these CI codes proved to be an efficient PAPR reduction method in multi-user variable rate communication systems [8]. In [9, 10], CI-OFDM scheme is referred as single-carrier modulation scheme due to the cancellation of phase and also the gain in PAPR is not just due to the complex spreading codes. However, the principle of multi-carrier modulation can be retained along with the advantage of low PAPR in CI-OFDM scheme by employing the oversampling technique in frequency domain. To the authors knowledge, the oversampled CI-OFDM scheme architecture presented in this paper is not available in the literature. Therefore, an efficient hardware architectural design and detailed implementation methodology of oversampled CI-OFDM baseband transceiver with two modulation schemes, i.e. binary phase shift keying (BPSK) and quadrature phase shift keying (QPSK) is proposed. For validating these transceivers in real-time hardware, they are prototyped on the FPGA device along with additive white Gaussian noise (AWGN) channel. Furthermore, the real-time oversampled CI-OFDM analog signal (with the two modulation schemes) is generated and compared with the MATLAB simulated signal of the proposed architecture.
Mitigation of DME interference in LDACS1-based future air-to-ground (A/G) communications
Published in Cogent Engineering, 2018
L-DACS1 supports two different ways of communication, one A/G communication and a second one for A/A communication. In our work, we mainly focus only on A/G communication. It supports the data communication and also supports the voice communication as optional. The A/G communication assumes star topology between the centralized GS and multiple aircrafts within the LDACS1 cell (i.e. operating range of GS). For the FL, the OFDM is chosen a modulation technique, whereas, in the RL, a combination of orthogonal frequency-division multiple access (OFDMA) and time-division multiple-access (TDMA) is applied. The FL and RL directions are separated by FDD. The LDACS1 and LDACS2 system parameters are depicted in Table 1 and OFDM parameters for LDACS1 are shown in TABLE 2. The large number of different combinations of modulation and coding techniques is used for modern communication system. Utilizing those, the transmission can be continuously adjusted to the channel condition, interference conditions, and user requirements. In LDACS1, the coding comprises of a Reed-Solomon (RS) code linked with a convolutional coding technique. As modulation technique, quadrature phase shift keying (QPSK) is used.
Secrecy sum-rate based illegitimate relay selection
Published in Australian Journal of Electrical and Electronics Engineering, 2023
where and represent the binary phase shift keying (BPSK) and the quadrature phase shift keying (QPSK) modulations, respectively. The BPSK modulation is considered for the performance analysis. Substituting the derived CDF expression into (26), the secrecy error probability metric’s analytical derivations can be obtained.