濾波器組多載波系統之濾波器設計使用半正定放寬以壓抑側瓣之峰值

Abstract

在許多5G或者6G的會議中，有限的頻寬資源常常是被探討的主題之一，在設計新的通訊系統過程中，我們總是需要將有效的使用頻寬資源的方法考慮進來，而較低的側瓣峰值等級/能量，也就是較低的頻帶外能量，是一個達到高頻譜效率的關鍵點。濾波器多載波系統的傳輸技術已被研究多年，且它在頻譜效能的表現上，要比現在主導寬頻多載波通訊系統領域多年的正交分頻多工系統還要來的好，也許濾波器多載波系統在未來有望能取代正交分頻多工的地位。 濾波器多載波系統的濾波器設計也已經被研究了幾年了，但在設計的過程中仍然有一些非必要的限制存在，如頻譜衰減。在我們的研究中，我們提出了一個嶄新設計濾波器的方式以匹配濾波器多載波系統/偏移正交振福調變系統，它有效的壓低側瓣峰值，也仍保留了近完美解調的性質。我們最後會在模擬結果中呈現在幅度響應和位元錯誤率測試上的表現。

Limited spectrum resources are usually the one of main topics covered in 5G or 6G conferences. The process of designing the novel communication system to fit the new regulation should be always concerned with the efficient usage of spectrum resources. Lower peak side-lobe level/power, i.e., lower out-of-band emission (OoBE), is the key point to achieving spectrum efficiency. The filter bank multicarrier (FBMC) transmission technique has been investigated for years, and the spectrum performance of FBMC outperforms the performance of orthogonal frequency division multiplexing (OFDM), a dominant transmission technique for broadband multicarrier communications in recent years. Perhaps FBMC could replace OFDM as a new communication system in the future. The filter design of FBMC has been researched for years, but there are still some drawbacks in the designing process such as constraints about spectrum decay. In our work, we propose a new method of designing the filter for the FBMC/OQAM system, which efficiently suppresses the peak side-lobe level, but still considers the property of near-perfect reconstruction. We would show the performance of the magnitude response and bit error rate (BER) test in our simulation result.