Design and implementation of digital Costas loop and Bit synchronizer in FPGA for BPSK demodulation

Roshna, T. R.; Nivin, R.; Joy, Sherly; Apren, T. J.; Alex, Valdivielso Chian

doi:10.1109/iccc.2013.6731621

Cited by 14 publications

(5 citation statements)

References 8 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Subsequently, it enters the Costas loop to obtain the coherent carrier signal oi (t). The filtered 2PSK input signal can written as [46],…”

Section: Sending Module Designmentioning

confidence: 99%

BECS-II: an updated bio-inspired electrocommunication system for small underwater robots

Chen,

He,

Xie

2023

Bioinspir. Biomim.

View full text Add to dashboard Cite

Some weakly electric fish can use electric signals to interact and communicate with each other in dark and complex underwater environments where traditional underwater communication fails. In our previous work, we developed a bio-inspired electrocommunication system (BECS) that serves as an effective alternative to traditional methods in this challenging underwater scenario performing communication at a speed of approximately 1200 bps (bits per second) within approximately 3 m. In this study, a novel underwater wireless communication system (BECS-II) is proposed to upgrade the BECS with much better performance. We first propose theoretical and simulation models for electrocommunication, including the effects of the angular frequency and electrode impedance. A custom-made digital communication system is employed in BECS-II to improve the anti-interference ability and channel capacity of the BECS. In addition, a novel circuit optimization strategy was used to develop a customized circuit to enhance the transmitting and receiving capabilities of the BECS-II. Dual-frequency communication is proposed to meet the communication demands of different tasks by taking inspiration from the task allocation and evolution mechanisms of weakly electric fish. The experimental results showed that BECS-II outperformed BECS in high-frequency mode at both the communication speed (approximately 20 kbps) and distance (approximately 10 m), whereas in low-frequency mode, it extended the communication range by transmitting data up to a distance of approximately 20 m at a speed of approximately 200 bps. A substantial increase in the communication distance can expand the robot motion space in a group and improve group flexibility.

show abstract

“…Subsequently, it enters the Costas loop to obtain the coherent carrier signal oi (t). The filtered 2PSK input signal can written as [46],…”

Section: Sending Module Designmentioning

confidence: 99%

BECS-II: an updated bio-inspired electrocommunication system for small underwater robots

Chen,

He,

Xie

2023

Bioinspir. Biomim.

View full text Add to dashboard Cite

show abstract

“…Reported solutions to recover constellation points for PSK and QAM waveforms are mainly based on PLL schemes, such as a Costas Loop [16] and a Square Loop [17], or through the maximum likelihood (ML) [18] method. All of which are using an equalization for undesirable channel effects in the signal preprocessing step (cf.…”

Section: Related Workmentioning

confidence: 99%

Adaptive Blind MPSK Constellation Recovery and Equalization for Cognitive Radio Applications

Marrero

Gómez

Dressler

et al. 2022

IEEE Trans. Veh. Technol.

View full text Add to dashboard Cite

Cognitive radio (CR) is considered a relevant communication paradigm to deal with the increasing demands in modern communications systems. Adaptive schemes are required to recognize channel conditions and to properly adjust main transmission parameters to improve the quality of communications. In this direction, blind algorithms to recover constellation, from phase-modulated signals, represent a means to implement cognitive capabilities to allow automatic modulation recognition (AMR) on receivers. Commonly, the most popular approaches for blind constellation recovery are based on a two-step scheme. The first step uses to equalize channel effects and reduce inter-symbol interference (ISI). The second step carries out constellation recovery utilizing phase locked loop (PLL) systems like the Costas Loop, then to classify the incoming signal. This work proposes a novel single-step blind adaptive filter solution, inspired by an adaptive interference canceler, for joint equalization and constellation symbol recovery from received phase shift keying (PSK) waveforms. Furthermore, we propose new coefficients update mechanisms based on the constant amplitude of PSK signals. The proposed solution exhibits reduced computational complexity compared to the state of the art and a reduced time of convergence. Additionally, the proposed scheme does not require a training sequence to operate properly. The obtained results clearly show that the proposed scheme significantly improves accuracy regarding phase symbol estimation and ISI reduction.

show abstract

“…The squaring recovery block [4] corrects any time error by interpolating the s C [n] signal in order to choose the best sample. The last block implements a digital Costas loop [5] that estimates and corrects the phase error and performs the bit decision.…”

Section: Demodulator Modelmentioning

confidence: 99%

New interpolator and data detector for full digital BPSK demodulator

Figueredo

Lucena

Mota

2014

2014 International Telecommunications Symposium (ITS)

View full text Add to dashboard Cite

This work presents a new structure for an alldigital BPSK demodulator developed for space communications that performs simultaneously the sampling and down conversion from intermediate frequency signal to the baseband signal. A new interpolator is proposed in order to simplify the demodulator implementation. This interpolator correlates the samples of the output signal in such way that it was necessary to design a new data detector appropriate to process the samples corrupted by gaussian and colored noise. The effects of the new interpolation at the noise are analyzed as well as the way it affects the whole demodulator performance. Simulations were performed and the results are presented to confirm theoretical analysis.

show abstract

Design and implementation of digital Costas loop and Bit synchronizer in FPGA for BPSK demodulation

Cited by 14 publications

References 8 publications

BECS-II: an updated bio-inspired electrocommunication system for small underwater robots

BECS-II: an updated bio-inspired electrocommunication system for small underwater robots

Adaptive Blind MPSK Constellation Recovery and Equalization for Cognitive Radio Applications

New interpolator and data detector for full digital BPSK demodulator

Contact Info

Product

Resources

About