Công nghệ SDR trong truyền thông di động trên thế giới

Ngày tải lên: 06/09/2015, 18:28

... chiếm giữ Ta gọi mapping sóng mang localized SC- FDMA localized FDMA ( LFDMA) gọi mapping distributed distributed FDMA (DFDMA) IFDMA trường hợp đặc biệt SC- FDMA hiệu chỗ phát điều chế tín hiệu hoàn ... mẫu SC- FDMA OFDMA có đầu vào điều chế QPSK, nắn dạng xung Về tổng thể, ba kỹ thuật mapping sóng mang đơn sóng mang cho công suất đỉnh thấp OFMD 3.4 SC- FDMA OFDMA Hình cho t...

Ngày tải lên: 01/04/2014, 11:53

... increasing need for function diversification will drive the programmable DSP into an even more integrated role within the mobile devices of tomorrow Nonprogrammable DSP architectures will have ... communicates audio information A display unit of some sort could be connected to the user’s eye glasses for communicating visual data And beyond these fairly new applications, medical sensors ......

Ngày tải lên: 01/07/2014, 17:20

... of DSP, without the associated design cost † DSPs are multitasking devices A DSP is a general purpose device As process technology improves, two different functions that were performed on two DSPs, ... modems, digital still camera, and solid-state audio players As was mentioned in Section 2.2, the power difference between DSP and ASIC solutions was significantly reduced by designing the...

Ngày tải lên: 01/07/2014, 17:20

... to the DSP through a standardized interface Therefore TCCs benefit from the DSP addressing capability, DSP address/data bus bandwidth, internal registers and common DSP memory space Additionally ... Channel Code Division Multiple Access Digital Base Band Delay Locked Loop Digital Signal Processor European Telecommunications Standards Institute Frequency Division Duplex General Packet R...

Ngày tải lên: 01/07/2014, 17:20

... they are closely related The most DSP intensive functions are the two types of channel decoding: convolutional decoding and turbo decoding Convolutional encoding is used for low data rate frames ... Memory C64x (MHz) Symbol rate encoding a Symbol rate decoding (excluding convolutional and turbo decoders) b Convolutional decoder Turbo decoder Total DSP only Total DSP coprocessors C64x FC...

Ngày tải lên: 01/07/2014, 17:20

... DSP solutions In many implementations the application of the linear combining weights as well as the computation of those weights are computed in real time in dedicated DSP hardware A block diagram ... vector v, indicates that the elements of the vector are placed in the diagonal of a square diagonal matrix of appropriate size For a matrix, the convention is adopted that dðMÞ is a diagona...

Ngày tải lên: 01/07/2014, 17:20

... the digital domain 6.3 Digitizing Today’s Analog Operations Digitizing operations currently performed in analog requires moving the Analog to Digital Converter (ADC) ever closer to the radio’s ... same piece of hardware with different parameters in different modes, whereas the second implies using the same piece of hardware for different types of processing, at different times The second, ......

Ngày tải lên: 01/07/2014, 17:20

... processing functions (a natural fit for DSP) : the use of a DSP plus a RISC, a RISC on its own or with a DSP co-processor, a DSP on its own or lastly a new integrated DSP/ RISC component The first time ... centered more on ‘‘disguising a RISC processor as a DSP ’ or using small DSP coprocessors In the case of the latter, the excess burden of the DSP 110 The Application of Programma...

Ngày tải lên: 01/07/2014, 17:20

... distributed Jvm in the context of multimedia applications This distributed Jvm first permits the use of a DSP to a Java application and second exploits the energy consumption features of the DSP ... performance 8.4.3 Distribution of Tasks and Management of Soft Real-Time Constraints Regarding the execution, our basic approach is to design a distribution rule that will transparently distrib...

Ngày tải lên: 01/07/2014, 17:20

... applications Improved coding efficiency can be obtained by coding the difference between consecutive samples, using a method called differential PCM (DPCM) In predictive coding, the difference that is ... various speech coding standards, and discuss issues relating to their implementation on DSPs 9.2 Speech Coder Attributes Speech coding consists of minimizing redundancies present in the digit...

Ngày tải lên: 01/07/2014, 17:20

... the different conditions The digit utterances consisted of 4-, 7- and 10-digit strings, the commands were 40 call and list management commands (e.g ‘‘return call’’, ‘‘cancel’’, ‘‘review directory’’) ... (SI) isolated digit recognition An SI speech recognizer does not need to be retrained on new speakers Isolated digits imply that the speaker inserts pauses between the individual digits † Spea...

Ngày tải lên: 01/07/2014, 17:20

... entered the audio coding arena with their Window Media Audio (WMA) player 11.3.3 Audio Coding on DSPs Today’s low-power DSPs provide the processing power and on-chip memory to enable audio applications ... within MPEG-4 audio for general audio coding Video and Audio Coding for Mobile Applications 195 the US for DVD and HDTV [17] Other audio codecs include Lucent’s EPAC, AT&T’s PAC, RealAudio’...

Ngày tải lên: 01/07/2014, 17:20

... consequence, with unpredictable time of answer (distributed platform: e.g connected wireless) In addition, the use of status events allows the application to react immediately to unexpected events ... is possible to download on the DBB data such as media files (video, audio – for example ringing melodies) The DBB will then handle some multimedia tasks, so it will have limited e-content applica...

Ngày tải lên: 01/07/2014, 17:20

... repeated attempts to gain access, or recording of the user’s voice However, recording of a user’s voice can be remedied by prompting the user to say different phrases each time a system performs ... Application of Programmable DSPs in Mobile Communications 222 This type of curve indicates that a verification system may operate over a variety of conditions, depending on the relative costs of .....

Ngày tải lên: 01/07/2014, 17:20