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Item type:Publication, Access status: without files , Error Bound Analysis of Chip-to-Chip Communication Based on Spectrum Shaping(2019-11); ; Spectrum shaping is a good candidate for improving the efficiency of chip-to-chip communication systems. In recent years, distinct spectrum shaping schemes have been proposed for different chip-to-chip communication channels. However, a general metric on the suitability of spectrum shaping schemes is still lacking. This work addresses the problem through theoretical analysis. Two methods are utilized in the investigation, capacity achievement and error probability minimization. For the first time to our knowledge, the relation between bit error probability (BEP) and spectrum shaping is analyzed for chip-to-chip communication systems. The results facilitate the error bounds calculation of different spectrum shaping schemes, which provides a good reference for the design on the strategy of spectrum shaping.Publicationtype: Conference Paper91 - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Access status: with files , A low complexity spectrum shaping scheme for substrate integrated waveguides based on spread reshaping code(2019-08-24); ; In the microwave and millimeter-wave transmission regions, substrate-integrated waveguide (SIW) is a very promising candidate for the development of circuits and components. The channel of the SIW is a bandpass or high pass filter. This characteristic impedes the conventional baseband transmission using nonreturn-to-zero pulse shaping scheme. As an alternative to using mixers to facilitate a passband transmission, this paper proposes a spectrum shaping scheme of low complexity for the channel of SIW, namely spread reshaping code. It aims at matching the spectrum of the transmit signal to the channel frequency response. It facilitates the transmission through the SIW channel while it avoids using carrier modulation and equalization. Simulations reveal a good performance of this scheme, such that, as a result, eye opening is achieved without any equalization or modulation for the respective transmission channels.Publicationtype: Journal Article426 282 - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Access status: without files , An Energy Efficient Spectrum Shaping Scheme for Substrate Integrated Waveguides(2019-06); ; In the microwave and millimeter-wave transmission region, substrate-integrated waveguide (SIW) is a very promising candidate for the development of circuits and components. An SIW mimics a rectangular waveguide by approximating the closed sidewalls with a via fence. This structure suppresses the low frequency components and makes the channel of the SIW a bandpass or high pass filter. This channel characteristic impedes the conventional baseband transmission using non-return-to-zero (NRZ) pulse shaping scheme. Therefore, mixers are commonly proposed to be used as carrier modulator and demodulator in order to facilitate a passband transmission. However, carrier modulation is not an energy efficient solution, because modulation and demodulation at high frequencies consume a lot of energy. For the first time to our knowledge, this paper proposes a spectrum shaping scheme of low complexity for the channel of SIW, namely spread reshaping code. It aims at matching the spectrum of the transmit signal to the channel frequency response. It facilitates the transmission through the SIW channel while it avoids using carrier modulation. Simulations reveal a good performance of this scheme, such that, as a result, eye opening is achieved without any receiver equalization or modulation for the respective transmission channels.Publicationtype: Conference Paper157 - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Access status: without files , Framed Repetition Code for High Speed Chip-to-Chip Communication in Multi-Drop Interfaces(2019-05); ; In today's chip-to-chip communication over multi-drop bus (MDB) interfaces, the trend of high-speed transmission has led to ever growing bandwidth requirements. An MDB channel is frequency-selective with deep notches at low frequencies, namely fnotch, which result from strong reflections at an MDB interface. In conventional chip-to-chip communication systems, the signal power is concentrated in the main lobe of the power spectral density (PSD), i.e., within |f|sNRZ, where fsNRZ - 1/T, is defined as the signal bandwidth. Limited by the complexity on the analog equalizer, fsNRZ fnotch should hold to avoid strong distortions of the transmit signal. To cope with this problem, conventional signal processing methods, such as digital equalization and error control coding, are undesired in this application scenario due to extremely tight power and latency constraints. A spectrum shaping scheme named framed repetition code was proposed for the MDB channel of a single strong reflection. It aims at matching the signal spectrum to the channel magnitude response |H(f)|. However, a solution for multi-reflection channels, which is more often encountered in MDB interfaces, has not yet been investigated. This paper proposes a novel code construction algorithm for multi-reflection MDB channels. The algorithm is designed based on the root mean square delay spread. Using the constructed framed repetition codes, the degradation due to the channel filtering is reduced significantly. Simulations reveal a good performance. The data rate in multi-reflection MDB channels is increased by a factor of 2.6 without using any equalization compared to the conventional non-return-to-zero (NRZ) transmission scheme.Publicationtype: Conference Paper213 - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Access status: without files , Redundant and non-redundant spectrum shaping schemes for reflection-limited chip-to-chip communicationIn today's chip-to-chip communication, the trend of high-speed transmission has led to ever growing bandwidth requirements. To cope with the resulting frequency-selective behavior of the transmission channel, conventional measures, such as digital equalization and error control coding, are undesired in this application scenario due to extremely tight power and latency constraints. Alternatively, this paper proposes different processing techniques of low complexity. They aim at matching spectrum of the transmit signal to the channel frequency response. For that purpose, two categories are investigated, namely pulse shaping and repetition coding. The performance of these schemes is assessed using two exemplary reflection-limited channel models, the multi-drop bus (MDB) channel and the substrate-integrated waveguides (SIW) channel. Simulations reveal a good performance of selected methods, such that, as a result, sets of suitable spectrum shaping schemes are presented for the respective transmission channels.Publicationtype: Conference Paper136 - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Access status: without files , Toward cost-efficient 100G metro networks using IM/DD, 10-GHz components, and MLSE receiverWe demonstrate the generation and transmission of 28-Gb/s data employing inexpensive, off-the-shelf, 10-GHz 3-dB bandwidth optical components, intensity modulation (IM), direct detection (DD), and a digital signal processing-based receiver over uncompensated fiber links. We prove that the proposed technology is an enabler for next-generation 100-G cost-efficient point-to-point dispersion compensation fiber (DCF)-free metro networks up to 80 km, as well as for multispan metro-ring networks up to 400 km, consisting of cascaded erbium-doped fiber amplifiers and DCFs as in real-field implementations. Key techniques to enable transmission are the employment of signal predistortion in the transmitter to compensate for the components' limited bandwidth, a maximum likelihood sequence estimator (MLSE)-based receiver, and a high-performance sampling phase adjustment algorithm. Furthermore, we show that performance can be optimized, while at the same time the complexity of the electronic dispersion compensation part is significantly reduced by exploiting a simplified variant of MLSE that makes use of a reduced number of states. Results in this paper reveal the potentiality of our proposed scheme for a low-cost transition to 100 Gb/s ( 4 × 28 Gb/s) wavelength division multiplexed, point-to-point, metro-core, and multispan metro-ring networks, employing inexpensive optical components and the traditional cost-efficient IM/DD scheme.Publicationtype: Journal Article31 - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Access status: without files , Conditions on degree distributions to compensate differential penalty by LDPC turbo decodingDifferential modulation causes a performance penalty compared to non-differential transmission, that can be diminished by a turbo loop between the differential demodulation and the forward error correction (FEC) decoder. To enhance this effect the low density parity check (LDPC) code has to be adjusted to this loop. Dependent on the used LDPC code the differential penalty can be completely or only partly overcome. In this paper we show under which conditions regarding code rate and complexity this penalty can be compensated completely. Therefore we use the extrinsic information transfer (EXIT) chart analysis and optimize the check edge degree distributions. We also show how we can construct LDPC codes that perform well in both the coherent and differential case. These codes are of interest, as in certain situation, like e.g. for a low quality channel estimation, due to fast changing channels, differential transmission is essential, while in other situations the channel estimation is sufficiently accurate to avoid differential transmission. Codes that perform well in both, the differential and coherent case allow to design only one code for both schemes. Finally we compare the optimized degree distributions in certain cases.Publicationtype: Conference Paper65