Real-time cyclostationary analysis for cognitive radio via software defined radio

Abstract

Cyclostationary analysis such as spectral correlation function (SCF) and spectral coherence function (SOF) has been accepted as an important tool in signal detection and radio frequency (RF) parameter estimation in cognitive radios. However, cyclostationary analysis requires extremely high resolution to fully observe the cyclic frequency features, leading to very high computational complexity and difficulty in real time implementation, especially on software defined radios where computational capability is limited. In this paper, we implement and demonstrate a real time SCF/SOF RF signal analyzer by adopting previously proposed two-stage dynamic resolution SCF/SOF estimation method using software defined radios. Specifically, high resolution SCF/SOF calculation is only performed near the expected cyclic feature locations obtained through a low complexity coarse estimation employing spectral analysis. This cyclostationary analysis based RF signal analyzer is capable of sensing the existence of primary users and estimating the carrier frequency and symbol rate accurately. Using Universal Software Radio Peripheral (USRP) software defined radio platform and GNU radio software, we implement and demonstrate such a cyclostationary analysis based RF signal analyzer in real time and validate the performance in realistic wireless communication channels.

Probabilistic Spectrum Sensing Based on Feature Detection for 6G Cognitive Radio: A Survey

“…In this way, the CFs of OFDM symbols and CPs can be identified on the SCD. In addition, the authors in [91] illustrate how for realistic PSK signals (including channel impairments such as Doppler shift), the SCF can determine the center frequency and bit rate. The CF for which the highest magnitude of the SCF is achieved, shows the estimated frequency's value.…”

CycloDSP: A cyclostationary signal analysis tool for GNU Radio

“…SDR solutions based on GNU Radio for real-time analysis of cyclostationary signals have been presented in some papers, mainly oriented to spectrum sensing for cognitive radio applications (see [16] for a recent survey on this topic). In [17] a GNU Radio solution for realtime estimation of cyclic features in the frequency domain is proposed, with particular attention to reducing the computational burden by a two-stage approach, composed by a coarse estimation stage, followed by a fine estimation stage carried out only in close proximity to the cycle features determined in the first stage. The main task of the algorithm proposed in [17] is to extract from the estimated cyclostationary features some signal parameters of interest, such as, e.g., the carrier frequency or the symbol rate.…”

Implementation and verification of cyclostationary feature detector for DVB‐T signals

“…Although such detectors have been the subject of extensive investigation including theoretical analysis and computer simulations [6][7][8][9][10][11][12][13][14][15], only few practical realisations have been reported. In [16] the measurements of cyclostationary features of single carrier signals have been presented, but no detector has been proposed. In [17,18] the spectral correlation function has been used to detect various kinds of signals in experimental set-ups.…”