中文摘要
現行4G頻段的使用率已經達到飽和,為了提升服務品質,在5G系統預計將會開放更多頻段來支援場景的應用。另外,在次6GHz的頻段下,資料傳輸率必須要達到最高1Gbps。相較於現行LTE的頻段,在次6GHz頻段進行資料傳輸時,會因採用高頻段傳輸而造成路徑損失的影響將進一步地增大,進而將減少細胞覆蓋率。因此,若5G基地台在相同的傳輸功率下,欲達到和LTE相同的覆蓋範圍,則巨量天線系統、波束成形、波束追蹤等技術皆不可或缺。為了達到基站共站,提出非均勻的波束成形技術來改善高頻率所造成的路徑損失效應。透過部份窄波束來集中能量以將訊號發送到較遠的位置;寬波束則運用於一般情況。為了提供高移動速度的需求,波束追蹤技術也將進一步地被探討。如此一來,可以減少基地台佈建成本,讓電信業者加速5G系統佈建。
Abstract
Due to the crowded frequency band in LTE systems, 5G system is expected to provide more frequency bands to improve service quality in more usage scenarios. In addition, in sub-6GHz band, the data transmission rate must be up to 1Gbps. However, as data transmission in sub-6GHz, due to the use of higher frequency, path loss will be increased, thereby reducing the cell coverage compared to the existing LTE systems. Hence, if 5G base station to provide the same cell coverage under the constraints of transmission power, these techniques such as massive MIMO, beamforming, and beam tracking are indispensable. To achieve the coexisting with LTE base station, a non-uniform beamforming pattern is proposed to compensate the path loss caused by high-frequency transmission. The proposed beam pattern includes narrow beams and wide beams. The narrow beams are used to concentrate the signal energy to send to a distant location; the wide beams are applied to the general case. Furthermore, to provide the demand for high mobility, the beam tracking technique will be further explored. As a result, the cost of deploying the 5G base station can be reduced and then the telecom operators can speed up the 5G system deployment.
關鍵詞(Key Words)
長期演進技術(Long Term Evolution;LTE)
第五代行動通訊(The Fifth Generation Mobile Communication)
巨量通訊(Massive MIMO)
波束成形(Beamforming)
波束追蹤(Beam Tracking)
相關檔案: 6GHz以下頻段之多天線波束成形技術研究(全文)