支援多輸入多輸出無線通訊應用之可參數化記憶體設計與實作

Abstract

隨著行動裝置的普及，相關之無線通訊標準亦持續推陳出新。這些通訊標準則大部分基於多輸入多輸出（MIMO）和正交分頻多工（OFDM）兩種技術，不同通訊標準間，雖於天線數、資料傳輸速率等參數設定略有不同，然而其所使用之主要硬體元件則相似性極高。為節省因應新通訊標準而開發對應之硬體平台的時間及資源，本研究試圖在無線通訊平台（Wirelsess Processing Unit）系統架構下，提出一個適用於多種無線通訊應用之可參數化配置記憶體架構，並予以實作。 本研究提出之可參數化配置記憶體架構，其特色如下：由Master CPU控制每次執行之通訊標準的重要參數；將無線通訊接收端的資料集中管理，以減少資料在不同處理單元間的傳送和複製時間；同時根據參數配置記憶體分區給不同類型資料存取；與合作處理資料之硬體如ALU、Memory-Based FFTProcessor，則可根據自行設計之存取介面至記憶體讀寫資料。 本研究可支援64~2048點的FFT運算，在512點以下最高支援八天線的資料量。同時提供FFT最高十六平行讀寫埠， ALU最高八平行讀寫埠，記憶體之最高讀寫速度可支援至250MHz。可根據天線數，FFT點數，FFT平行度，Symbol傳送速度等參數，配置適當大小的分區記憶體和連接埠以供存取。另外在記憶體的控管上亦較有彈性，在接收讀寫請求時，可進行動態的記憶體分配與釋放。透過本研究自定的請求格式，存取可定位至symbol中的一個word。

With the the popularization of mobile devices, some related wireless communication specification also continues to bring forth the new through the old. These communicarion are mostly based on two techniques, MIMO(Multi-Input Mul-ti-Output) and OFDM(Orthogonal Frequency Division Multiplexing). Despite differ-ent standards have various parameter settings (such as the number of antennas, symbol rate), their requirements of major hardware components are highly similar. For saving time and resource when developing a corresponding hardware platform of newer communication specifications, this work proposed and implemented a scalable memory architecture which is adaptive to multiple wireless application under the WPU (Wireless Processing Unit) platform’s architecture. The characteristics of parameter-configurated memory architecture in this work are described below. After a master CPU initialize the essential parameters of executed specifications,the proposed memory could collect and manage the symbol data from OFDM baseband receiver, thus decrease the data transmission/copy time among different processing units.And this work could also set memory partition for data at diverse stages.For cooperative data processing hardwares such as ALU, memory-based FFT Processor, they could access data from the proposed memory according to our defined interface. The proposed memory support FFT operation between 64~2048 points.Under 512points it support 8 antennas at most. This work provides 16 parallel read/write ports for FFT Processor and 8 parallel read/write port for ALU, the accessing bandwidth of memory is up to 250MHz.Base on the number of antenna, FFT points, FFT paths, and symbol transmission rate, the proposed memory could offer suitable address space and enough connecting ports. Besides, the memory management is more flexible. When controller received read/write request, it could dynamically allocated/release memory space. According to our defined request format, the symbol data could locate to single word at minimum unit.