摘 要: 針對數字集群通信系統業務多樣性的需求,對原有產品進行了升級,設計了一種數字集群智能手機設備。首先,手機基帶單元以OMAP3530處理器為核心,可加載開放的操作系統;其次,對射頻單元的接收通路與發射通路進行優化設計,論述了接收靈敏度和發射功率兩個關鍵指標。實驗表明硬件平臺的處理能力獲得大幅提升,同時,射頻性能得到優化,使手機業務功能的擴展成為可能。
關鍵詞: OMAP3530; 寬帶業務; 接收靈敏度; 發射增益
中圖分類號: TN713?34; TP311 文獻標識碼: A 文章編號: 1004?373X(2013)13?0080?04
Design of digital trunking smartphone hardware
NIU Jin?hang, LIU Yu?bao, WU Guo?qiao
(North China Institute of Computing Technology, Beijing 100083, China)
Abstract: According to the diverse demands of digital trunking communication system services, the original product is upgraded and a digital trunking smartphone is designed. Firstly, the phone baseband unit which can load open operating system is designed based on OMAP3530. Secondly, both the receiving channel and transmit path of RF unit gain optimal design and two key indicators of the receiving sensitivity and transmit power are dissertated. Results show that the processing capacity of hardware platform gets improved significantly and RF performance is optimized, so the extension of mobile phone function becomes possible.
Keywords: OMAP3530; broadband service; receiving sensitivity; transmitting gain
0 引 言
隨著數字集群通信系統向寬帶化發展,集群寬帶業務實現成為可能,如視頻監控、可視電話、地理信息獲取等,這就要求數字集群終端由簡單功能型向智能型轉變[1]。目前使用的數字集群手機處理器性能較低,業務以話音、短信為主,手機系統封閉,用戶不能自行定制應用,已經越來越不能滿足用戶的需求。
本文對原有產品進行了改進,基于TI公司高性能雙核架構處理器OMAP3530(ARM+DSP)設計了一種數字集群智能手機,設備硬件資源充足,操作系統開放,能夠滿足數字集群通信寬帶業務的擴展性需求。另外,基于手持設備小型化、低功耗、低成本的考慮,手機射頻收發通路選用集成度高的低功耗器件實現信號的上下變頻及濾波處理,通過在OMAP3530內編程靈活控制射頻前端,完成頻率變換、功率控制等功能。
1 硬件平臺總體架構
數字集群智能手機采用模塊化設計,整機由天饋單元、射頻處理單元、基帶處理單元、人機交互單元、保密單元、SIM卡單元及電源七部分組成。……