DVB-T2 Receiver Research Articles

Investigative Assessment of the Impact of Perturbations on the Digital Terrestrial Television Broadcasting Signal

This study examines the effects of perturbations on the digital terrestrial television broadcasting (DTTB) signal in Jos, Plateau State, Nigeria, using measurement-based performance analysis. In order to examine the effects of environmental perturbations on DTTB signal, measurement campaign used the Nigerian Television Authority, Integrated Television Services (ITS) digital video broadcasting -second generation (DVB-T2) signal. The aim of the research was to identify the environmental and atmospheric perturbations with highest impact on DTTB signal. Field measurement was accurately obtained throughout the measurement campaign using the E8000 series spectrum analyzer, a DVB-T2 receiver, and other facilities in order to actualize the two important measurement characteristics, such as field strength and received signal strength (RSS). The outcome showed a significant amount of dips in route A, depriving towns surrounding rocky hills of a DVB-T2 signal, as demonstrated in the Du community with RSS values of -87.1 dBm, 85.2 dB , and -27.8 dB V/m, -23.9 dB V/m for field strength. Additionally, the results show that signal performance was better in the dry season compared to the rainy season (more primary coverage in the dry season compared to the rainy season), with the RSS value being -41.6 dBm versus -36.4 dBm and the field strength value being 34 dB/m versus 38.6 dB/m for route A, or the same on route B. Solving signal propagation issues requires understanding the fundamental metrics driving an increase in perturbations in any broadcast environment. Creating a model to address these issues will help with system evaluation, network planning, and broadcast service operation, ensuring quality of service (QoS).

Picture-Based Multiple-AntennaTechnique for the DVB-T2 Receiver

Abstract Deep-fading can decline the quality of the received signal to below threshold, and interrupts the reception-success (generating an outage or time-out). In DVB-T2 (Digital Video Broadcasting Terrestrial Second Generation) receiver, such interruption can be identified from the displayed-picture. Multiple-antenna is one of techniques to mitigate such problem. This paper presents a multiple-antenna method for receiving the DVB-T2 signal. At any time, one of antennas is selected where the selection action is controlled by the recovered-picture. In case of using two antennas, field-measurement was conducted to collect the real data, later used in the simulation of the proposed algorithm. The result showed its capability to increase the portion of cumulative reception-success duration up to approximately 1.53 times with respect to its equivalent single-antenna.

Influence of the LTE System using Cognitive Radio Technology on the DVB-T2 System using Diversity Technique

In recent years, the development of advanced wireless communication systems has been rapidly progressing. In Europe, the 2nd Generation Terrestrial Digital Video Broadcasting (DVB-T2) and Long-Term Evolution (LTE) are the most promising techniques to provide multimedia services efficiently (in flexible quality and with high spectrum efficiency). The purpose of this work is to explore possible influences of the LTE uplink services, using cognitive radio (CR) technology, on the area which is covered by DVB-T2 services. In the case of DVB-T2, both single-input single-output (SISO) and multiple-input single-output (MISO) transmission techniques are considered. The defined coexistence scenarios are measured with an appropriate measurement testbed. The performance of the received TV signal is evaluated on its physical layer (PHY) level. The obtained results allow better understand the influence of LTE system on DVB-T2 which is using diversity technique in the same RF channel (co-channel coexistence). One of the main results is that there are the same requirements on the Forward Error Correction (FEC) decoding process in the DVB-T2 receiver, when power imbalances between TV transmitters (an both SISO and MISO modes) are considered at the interfering LTE signal. This finding was also proved by analysis of variance (ANOVA).

L1 signaling mobility performance in the DVB-T2 receivers intercarrier interference cancellation method applied to L1 signaling

In this paper, DVB-T2 mobility performance for both payload and signaling is analyzed and a method to improve the L1 signaling behavior in a mobile scenario is presented by means of applying an intercarrier interference (ICI) cancellation algorithm. This method allows the signaling to support a higher Doppler spread and widening the set of configurations that can be supported.

An area-efficient Radix 28 FFT algorithm for DVB-T2 receivers

This paper presents an area-efficient variable-length FFT algorithm for DVB-T2 receivers. A matrix-based approach is used to achieve a novel radix 28 algorithm that fulfils the DVB-T2 specifications. Several implementation techniques are proposed to apply in order to reduce the FFT core area, such as a variable datapath scaling approach, a memoryless CORDIC algorithm and an efficient FIFO implementation. The layout of the FFT processor is designed in XFAB 0.18μm CMOS technology. The proposed variable-length processor occupies a layout area of 6.75mm2. Compared with the DVB-T2 designs in the literature, the proposed FFT processor presents the most area-efficient implementation. Furthermore, it provides a good power efficiency in the lower modes.

One-Dimensional Soft-Demapping Algorithms for Rotated QAM and Software Implementation on DSP

To improve detection performance of quadrature amplitude modulation (QAM), signal space diversity (SSD) has been exploited and adopted for the second generation of digital video broadcasting (DVB-T2) system. Maximum-likelihood detection (MLD) to get full SSD is avoided because of enormous computational complexity. Its max-log approximated detection (full search algorithm) and subregion based soft-demappers are also too complex to be implemented due to their two-dimensional (2D) Euclidean distance calculation. In particular, the complexity becomes the main burden for the software implementation, which is attractive for multistandard broadcasting receivers. To tackle the main bottleneck, we propose one-dimensional (1D) soft-demappers. By reformulating a rotated QAM signal as two layered pulse amplitude modulation (PAM) signals, the full search algorithm is simplified to an MMSE decorrelation followed by 1D soft-demapping, where Gaussian approximation is used for the interferences. Additional interference cancellation is considered to further suppress its residual interference. For 256-QAM with 4/5 code rate in memoryless Rayleigh channels with/without erasures, the performance gap to the full search is within 0.15 dB at 10 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">-3</sup> bit error rate (BER), while the complexity is less than 8%. Due to the significant complexity reduction of the proposed algorithms, the software implementation of a DVB-T2 receiver on DSP is feasible with 73% less computations than the one with the full-search-based soft-demapper.

Software-defined DVT-T2 demodulator using scalable DSP processors

This paper describes the feasibility of software-defined demodulator of DVB-T2 standard using the scalable DSP processor. This paper focuses mainly on the DVB-T2 receiver design and implementation of four major software blocks of the demodulator: FFTs, channel estimator, multi-level de-interleavers and rotated QAM soft-demapper. In particular, 2K-point FFT function is analyzed and mapped on the scalable architecture of coarse-grained reconfigurable array (CGRA) processors resulting 51dB signal to quantization noise ratio (SQNR) performance. The computational burden of frequency interpolator and frequency/cell deinterleavers are greatly reduced with specially designed intrinsics, 30% and 85%, respectively, from the original implementation. The softdemapper for rotated QAM constellation becomes feasible with the latest 1D-MMSE decorrelation method though it is still the most expensive function covering 40% of DTG106 mode. By implementing full chain demodulation software including abovementioned four major functions, it is demonstrated that the software-defined DVB-T2 demodulator is realizable with software on two scalable CGRA processors running at 300MHz.

Improved synchronization, channel estimation, and simplified LDPC decoding for the physical layer of the DVB-T2 receiver

The newly developed 2nd generation standard for digital video broadcasting (DVB-T2) emerges as a significant upgrade over its first generation predecessor DVB-T. The DVB-T2 standard targets an increased system throughput by at least 30% over the DVB-T. This article introduces algorithms in the signal processing chain to improve the mobile operation for DVB-T2. The proposed modified synchronization blocks, along with the improved channel estimation, show significant improvement compared to the results reported in the DVB-T2 implementation guide. In addition, state-of-the-art low-complexity algorithms in the bit processing chain, particularly in the LDPC decoder, are used to provide robustness and support throughput increase, while reducing the implementation complexity. The integrated system is simulated including implementation effects. The simulation results confirm the enhanced performance of the developed integrated model and provide better results compared to those reported in literature.

Beamforming Based Receiver Scheme for DVB-T2 System in High Speed Train Environment

In this paper, the received signal from the different base stations (BSs) of the second generation of Terrestrial Digital Video Broadcasting (DVB-T2) in the high-speed-train (HST) scenario is modeled as a fast time-varying signal with the multiple Doppler frequency offsets. The interference caused by the multiple Doppler frequency offsets and the channel variations, and the signal to interference plus noise ratio of the received signal, are derived for the DVB-T2 receiver. The results of the theoretical analysis show that the interference greatly degraded the performance of the DVB-T2 system. To suppress the interference, we proposed a beamforming based receiver scheme for DVB-T2 system. By using the new signal processing scheme for the received signal vector from the antenna array, one can separate the received signal with the multiple Doppler frequency offsets into the multiple signals, each of which is with a single Doppler frequency offset. The separated signals are compensated by the corresponding Doppler frequency offsets and equalized by the estimated channel responses respectively, then combined into a signal to be demodulated. The results of the simulation show that the proposed scheme can effectively suppress the interference and greatly improve the performance of the DVB-T2 system in the HST environment.

BICM기반의 DVB-T2 수신기 성능분석

In this paper, a DVB-T2(Digital Video Broadcasting-the 2nd Generation Terrestrial) receiver is designed under a USB-type windows environment, and the baseband frames for MPEG2-TS stream(File or Ethernet Modes) are analyzed for verifying the receiver. In addition, the performance of the BICM(Bit Interleaved Coding & Modulation) module in the receiver is analyzed in terms of PLP(Physical Layer Pipe) and L1(Layer 1) signals.

Iterative Detection and ICI Cancellation for MISO-mode DVB-T2 System with Dual Carrier Frequency Offsets

In the DVB-T2 system with a multiple-input single-output (MISO) transmission mode, Alamouti coded orthogonal frequency division multiplexing (OFDM) signals are transmitted simultaneously from two spatially separated transmitters in a single frequency network (SFN). In such systems, each transmit-receive link may have a distinct carrier frequency offset (CFO) due to the Doppler shift and/or frequency mismatch between the local oscillators. Thus, the received signal experiences dual CFOs. This not only causes dual phase errors in desired data but also introduces inter-carrier interference (ICI), which cannot be removed completely by simply performing a CFO compensation. To overcome this problem, this paper proposes an iterative detection with dual phase errors compensation technique. In addition, we propose a successive-iterative ICI cancellation technique. This technique successively eliminates ICI in the initial iteration by exploiting pre-detected data pairs. Then, in subsequent iterations, it performs a fine interference cancellation using a priori information, iteratively fed back from the channel decoder. In contrast to previous works, the proposed techniques do not require estimates of dual CFOs. Their performances are evaluated via a full DVB-T2 simulator. Simulation results show that the DVB-T2 receiver equipped with the proposed dual phase errors compensation and the successive-iterative ICI cancellation techniques achieves almost the same performance as ideal dual CFOs-free systems, even for large dual CFOs.

Complexity analysis of software defined DVB-T2 physical layer

The second generation terrestrial TV broadcasting standard from the digital video broadcasting (DVB) project, DVB-T2, has recently been standardized. In this article we perform a complexity analysis of our software defined implementation of the modulator/demodulator parts of a DVB-T2 transmitter and receiver. First we describe the various stages of a DVB-T2 modulator and demodulator, as well as how they have been implemented in our system. We then perform an analysis of the computational complexity of each signal processing block. The complexity analysis is performed in order to identify the blocks that are not feasible to run in realtime on a general purpose processor. Furthermore, we discuss implementing these computationally heavy blocks on other architectures, such as GPUs (graphics processing units) and FPGAs (field-programmable gate arrays), that would still allow them to be implemented in software and thus be easily reconfigurable.

Comparison of area-efficient FFT algorithms for DVB-T2 receivers

Comparison at implementation level of several pipeline-SDF radix 2k FFT architectures is proposed in order to obtain efficient algorithms for DVB-T2 receivers. In the analysis, the area and performance of the algorithms are compared. A variable datapath optimisation has been added to the comparison.