ANALISIS PENERAPAN METODE PULSE SHAPING PADA SISTEM ORTHOGONAL FREQUENCY DIVISION MULTIPLEXING(OFDM) DALAM MEREDUKSI INTERCARRIER INTERFERENCE(ICI)

ABSTRAKSI: Orthogonal Frequency Division Multiplexing (OFDM) merupakan teknik modulasi multicarrier yang kini banyak digunakan pada komunikasi wired dan wireless dikarenakan kecepatan data transmisinya yang cukup tinggi dan efisiensi bandwidth yang tinggi pula dibandingkan dengan teknologi konvensional FDM. Namun OFDM sangat rentan terhadap penurunan ortoghonalitas dari subcarrier yang ditandai dengan adanya frequency offset sehingga terjadi Intercarrier Interference (ICI). Penyebab frequency offset adalah doppler shift dan juga disebabkan adanya perbedaan antara frekuensi osilator di penerima dan di pemancar. Maka diperlukan suatu solusi untuk mereduksi ICI untuk meningkatkan performansi sistem OFDM tersebut dan dalam Tugas Akhir ini dilakukan evaluasi kembali terhadap metode pulse shaping sebagai metode pereduksiannyaPada spektrum frekuensi OFDM setiap subcarrier-nya memiliki main lobe dan beberapa side lobe. Ketika terjadi penurunan orthogonalitas maka beberapa sidelobe tersebut akan memberikan dampak ICI. Tujuan dari pulse shaping ini adalah untuk mengurangi pengaruh side lobe yang menghasilkan daya ICI tersebut . Dalam simulasi dibandingkan antara jenis pulse yang konvensional yaitu rectangular pulse dengan metode pulse shaping menggunakan jenis Improved Sinc Power (ISP) pulse pada sistem mobile Wimax.Hasil simulasi menunjukkan bahwa penggunaan metode pulse shaping dengan ISP pulse memberikan peningkatan kinerja dari OFDM ketika adanya frequency offset yang terlihat dari grafik Bit Error Rate (BER) terhadap Eb/No jika dibandingkan dengan OFDM konvensional. Perbaikan kinerja tersebut berkisar ±2 dB hingga lebih dari 6 dB untuk BER target sebesar 10-4. Kemudian Nilai Eb/No yang dibutuhkan untuk mencapai BER 10-4 adalah paling kecil sebesar 15 dB.Kata Kunci : OFDM, ICI , BER, ISP , pulse shaping, frequency offsetABSTRACT: Orthogonal Frequency Division Multiplexing (OFDM) is multicarrier modulation technique which has been applied for wired and wireless communication systems due to its high data rate transmission capability with high bandwidth efficiency compared FDM technology. But OFDM is sensitive to attenuation orthogonality of subcarrier which cause by frequency offset and Intercarrier Interference(ICI) is present. Its causes by Doppler Shift and mismatch oscillator between transmitter and receiver. So , the reduction of ICI is needed to performance enhancement of OFDM system and the proposed method is using pulse shaping. In the OFDM spectrum each subcarrier consists of a main lobe and followed by a number of side lobes. When orthogonality lost, the side lobes cause ICI. The purpose of pulse shaping is to reduce the side lobe ,as the side lobes contains the ICI power. In the simulation will compare the rectangular pulse as the conventional and pulse shaping with the Improved Sinc Power Pulse(ISP) in mobile Wimax system.The result of simulation shows that using pulse shaping with ISP pulse make the better performance of OFDM when frequency offset is present which its show by the Bit Error Rate(BER) to Eb/No. It provide improvements range ±2 dB to over 6 dB for a target BER 10-4. And then, when the value of Eb/No used 15 dB performance achieved BER 10-4.Keyword: OFDM, ICI, BER, ISP, pulse shaping, frequency offse

Peak to Average Power Ratio Reduction in OFDM Using Pulse Shaping Technique

Orthogonal Frequency Division Multiplexing (OFDM) is a special type of multicarrier modulation in which a signal is split into several narrowband channels at different frequencies. Here data is divided into parallel data streams each transmitted on a separate band. One of the major drawbacks of multicarrier transmission is the high peak-to-average power ratio (PAPR) of the transmit signal. Nyquist filters provide ISI-free transmission. In this paper we are going to propose some new filters which can formulated in an effort to reduce the peak-to-average power ratio (PAPR) of the baseband signal. While maintaining the same excess bandwidth and the zero inter-symbol interference condition. The proposed filters contain various parameters which gives an additional degree of freedom to minimize PAPR for a given roll-off factor α

INTER CARRIER INTERFERENCE AND SIGNAL TO INTERFERENCE RATIO OF VARIOUS PULSE SHAPING FUNCTIONS USED IN OFDM SYSTEM WITH CARRIER FREQUENCY OFFSET

Orthogonal Frequency Division Multiplexing (OFDM) is the important modulation of choice for fourthgeneration broadband multimedia wireless systems. This paper is focused on the problem of reducing the intercarrierinterference (ICI) and signal to noise ratio in the transmission over OFDM using various pulse shaping methods. Here we have performed a detailed performance comparison of various pulse shaping functions used in OFDM System with Carrier Frequency Offset. They appear to be suitable for transmission in OFDM systems with carrier frequency offset. The results obtained by analysis show that the performance improvement over conventional pulse shapes, are significant for reducing average intercarrier-interference (ICI) power and increased ratio of average signal power to average ICI power (SIR)

Waveform Design for 5G and Beyond

5G is envisioned to improve major key performance indicators (KPIs), such as peak data rate, spectral efficiency, power consumption, complexity, connection density, latency, and mobility. This chapter aims to provide a complete picture of the ongoing 5G waveform discussions and overviews the major candidates. It provides a brief description of the waveform and reveals the 5G use cases and waveform design requirements. The chapter presents the main features of cyclic prefix-orthogonal frequency-division multiplexing (CP-OFDM) that is deployed in 4G LTE systems. CP-OFDM is the baseline of the 5G waveform discussions since the performance of a new waveform is usually compared with it. The chapter examines the essential characteristics of the major waveform candidates along with the related advantages and disadvantages. It summarizes and compares the key features of different waveforms.Comment: 22 pages, 21 figures, 2 tables; accepted version (The URL for the final version: https://onlinelibrary.wiley.com/doi/abs/10.1002/9781119333142.ch2

Pulse shaping methods for inter carrier interference reduction in OFDM system

The weakness of the orthogonal freuency division multiplexing (OFDM) system is susceptible to the existence of carrier frequency offset (CFO) which causes the emergence of inter carrier interference (ICI) which causes a degradation of performance OFDM systems. This study aims to apply the suggested rectangular (REC) pulse and improved sinc-power (ISP) pulse shaping methods on OFDM system and determines ICI reduction with the effects of CFO over flat fading Rayleigh channels. The performance of each pulse shaping method is evaluated and compared based on parameter ICI power vs. normalized frequency offset, signal to interference ratio (SIR) vs. normalized frequency offset and bit error rate (BER) vs. energy bit per noise (Eb/No). The simulation result in terms of BER vs. Eb/No indicated that REC and ISP pulse shaping has better performance dealing with ICI reduction compared to OFDM system no applied pulse shaping. In addition, the ISP is able to mitigate ICI better than REC

On Max-SINR Receiver for Hexagonal Multicarrier Transmission Over Doubly Dispersive Channel

In this paper, a novel receiver for Hexagonal Multicarrier Transmission (HMT) system based on the maximizing Signal-to-Interference-plus-Noise Ratio (Max-SINR) criterion is proposed. Theoretical analysis shows that the prototype pulse of the proposed Max-SINR receiver should adapt to the root mean square (RMS) delay spread of the doubly dispersive (DD) channel with exponential power delay profile and U-shape Doppler spectrum. Simulation results show that the proposed Max-SINR receiver outperforms traditional projection scheme and obtains an approximation to the theoretical upper bound SINR performance within the full range of channel spread factor. Meanwhile, the SINR performance of the proposed prototype pulse is robust to the estimation error between the estimated value and the real value of time delay spread.Comment: 6 pages. The paper has been published in Proc. IEEE GLOBECOM 2012. Copyright transferred to IEEE. arXiv admin note: text overlap with arXiv:1212.579

ICI and PAPR enhancement in MIMO-OFDM system using RNS coding

The Inter-Carrier-Interference (ICI) is considered a bottleneck in the utilization of Multiple-Input-Multiple-Output Orthogonal Frequency Division Multiplexing (MIMO-OFDM) systems, due to the sensitivity of the OFDM towards frequency offsets which lead to loss of orthogonality, interference and performance degradation. In this paper Residue Numbers as a coding scheme is impeded in MIMO-OFDM systems, where the ICI levels is measured and evaluated with respect to conventional ICI mitigation techniques implemented in MIMO-OFDM. The Carrier-to-Interference Ratio (CIR), the system Bit-Error-Rate (BER) and the Complementary Cumulative Distribution Function (CCDF) for MIMO-OFDM system with Residue Number System (RNS) coding are analyzed and evaluated. The results had demonstrated a performance of transmission model with and without RNS