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39-758: UMTS Terrestrial Radio Access Network ( UTRAN ) is a collective term for the network and equipment that connects mobile handsets to the public telephone network or the Internet. It contains the base stations, which are called Node B 's and Radio Network Controllers (RNCs) which make up the Universal Mobile Telecommunications System (UMTS) radio access network . This communications network, commonly referred to as 3G (for 3rd Generation Wireless Mobile Communication Technology), can carry many traffic types from real-time Circuit Switched to IP based Packet Switched . The UTRAN allows connectivity between

78-547: A DSP is usually to measure, filter or compress continuous real-world analog signals . Most general-purpose microprocessors can also execute digital signal processing algorithms successfully, but may not be able to keep up with such processing continuously in real-time. Also, dedicated DSPs usually have better power efficiency, thus they are more suitable in portable devices such as mobile phones because of power consumption constraints. DSPs often use special memory architectures that are able to fetch multiple data or instructions at

117-521: A DSP optimized instruction set. One implication for software architecture is that hand-optimized assembly-code routines (assembly programs) are commonly packaged into libraries for re-use, instead of relying on advanced compiler technologies to handle essential algorithms. Even with modern compiler optimizations hand-optimized assembly code is more efficient and many common algorithms involved in DSP calculations are hand-written in order to take full advantage of

156-497: A broad range of external peripherals and various buses (PCI/serial/etc). TMS320C6474 chips each have three such DSPs, and the newest generation C6000 chips support floating point as well as fixed point processing. Freescale produces a multi-core DSP family, the MSC81xx. The MSC81xx is based on StarCore Architecture processors and the latest MSC8144 DSP combines four programmable SC3400 StarCore DSP cores. Each SC3400 StarCore DSP core has

195-516: A clock speed of 1 GHz. XMOS produces a multi-core multi-threaded line of processor well suited to DSP operations, They come in various speeds ranging from 400 to 1600 MIPS. The processors have a multi-threaded architecture that allows up to 8 real-time threads per core, meaning that a 4 core device would support up to 32 real time threads. Threads communicate between each other with buffered channels that are capable of up to 80 Mbit/s. The devices are easily programmable in C and aim at bridging

234-516: A lower-cost solution, with better performance, lower latency, and no requirements for specialised cooling or large batteries. Such performance improvements have led to the introduction of digital signal processing in commercial communications satellites where hundreds or even thousands of analog filters, switches, frequency converters and so on are required to receive and process the uplinked signals and ready them for downlinking , and can be replaced with specialised DSPs with significant benefits to

273-513: A new breed of DSPs offering the fusion of both DSP functions and H/W acceleration function is making its way into the mainstream. Such Modem processors include ASOCS ModemX and CEVA's XC4000. In May 2018, Huarui-2 designed by Nanjing Research Institute of Electronics Technology of China Electronics Technology Group passed acceptance. With a processing speed of 0.4 TFLOPS, the chip can achieve better performance than current mainstream DSP chips. The design team has begun to create Huarui-3, which has

312-526: A special instruction set, with instructions like load-and-accumulate or multiply-and-accumulate. It could work on 16-bit numbers and needed 390 ns for a multiply–add operation. TI is now the market leader in general-purpose DSPs. About five years later, the second generation of DSPs began to spread. They had 3 memories for storing two operands simultaneously and included hardware to accelerate tight loops ; they also had an addressing unit capable of loop-addressing. Some of them operated on 24-bit variables and

351-523: A specific task, ranging in price from about US$ 1.50 to US$ 300. Texas Instruments produces the C6000 series DSPs, which have clock speeds of 1.2 GHz and implement separate instruction and data caches. They also have an 8 MiB 2nd level cache and 64 EDMA channels. The top models are capable of as many as 8000 MIPS ( millions of instructions per second ), use VLIW ( very long instruction word ), perform eight operations per clock-cycle and are compatible with

390-468: A technology that had previously not been mass-produced. It was designed as a microprocessor peripheral, for the Motorola 6800 , and it had to be initialized by the host. The S2811 was not successful in the market. In 1979, Intel released the 2920 as an "analog signal processor". It had an on-chip ADC/DAC with an internal signal processor, but it didn't have a hardware multiplier and was not successful in

429-462: A typical model only required about 21 ns for a MAC. Members of this generation were for example the AT&;T DSP16A or the Motorola 56000 . The main improvement in the third generation was the appearance of application-specific units and instructions in the data path, or sometimes as coprocessors. These units allowed direct hardware acceleration of very specific but complex mathematical problems, like

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468-622: A very popular deployment). Digital signal processor A digital signal processor ( DSP ) is a specialized microprocessor chip, with its architecture optimized for the operational needs of digital signal processing . DSPs are fabricated on metal–oxide–semiconductor (MOS) integrated circuit chips. They are widely used in audio signal processing , telecommunications , digital image processing , radar , sonar and speech recognition systems, and in common consumer electronic devices such as mobile phones , disk drives and high-definition television (HDTV) products. The goal of

507-484: Is changing with the emergence of High Speed Downlink Packet Access ( HSDPA ), where some logic (e.g., retransmission) is handled on the Node B for lower response times. The utilization of WCDMA technology allows cells belonging to the same or different Node Bs and even controlled by different RNC to overlap and still use the same frequency (in fact, the whole network can be implemented with just one frequency pair ). The effect

546-459: Is generally easier to implement algorithms in floating point. Generally, DSPs are dedicated integrated circuits; however DSP functionality can also be produced by using field-programmable gate array chips (FPGAs). Embedded general-purpose RISC processors are becoming increasingly DSP like in functionality. For example, the OMAP3 processors include an ARM Cortex-A8 and C6000 DSP. In Communications

585-714: Is rarely the only task of a system. Some useful features for optimizing DSP algorithms are outlined below. By the standards of general-purpose processors, DSP instruction sets are often highly irregular; while traditional instruction sets are made up of more general instructions that allow them to perform a wider variety of operations, instruction sets optimized for digital signal processing contain instructions for common mathematical operations that occur frequently in DSP calculations. Both traditional and DSP-optimized instruction sets are able to compute any arbitrary operation but an operation that might require multiple ARM or x86 instructions to compute might require only one instruction in

624-420: Is utilized in soft handovers . Since WCDMA often operates at higher frequencies than GSM (2,100 MHz as opposed to 900 MHz for GSM), the cell radius can be considerably smaller for WCDMA than for GSM cells as the path loss is frequency dependent. WCDMA now has networks operating in the 850–900 MHz band. In these networks, at these frequencies, the coverage of WCDMA is considered better than that of

663-690: The Radio Network Subsystem (RNS). There can be more than one RNS present in a UTRAN. There are four interfaces connecting the UTRAN internally or externally to other functional entities: Iu, Uu, Iub and Iur. The Iu interface is an external interface that connects the RNC to the Core Network (CN). The Uu is also external, connecting Node B with the User Equipment (UE). The Iub is an internal interface connecting

702-527: The Speak & Spell concept to Paul Breedlove, Larry Brantingham, and Gene Frantz at Texas Instruments ' Dallas research facility. Two years later in 1978, they produced the first Speak & Spell, with the technological centerpiece being the TMS5100 , the industry's first digital signal processor. It also set other milestones, being the first chip to use linear predictive coding to perform speech synthesis . The chip

741-542: The UE (user equipment) and the core network . The RNC provides control functionalities for one or more Node Bs. A Node B and an RNC can be the same device, although typical implementations have a separate RNC that is located in a central office serving multiple Node Bs. Despite the fact that they do not have to be physically separated, there is a logical interface between them known as the Iub. The RNC and its corresponding Node Bs are called

780-575: The DSP core is hidden as a fixed-function block into a SoC , but NXP also provides a range of flexible single core media processors. The TriMedia media processors support both fixed-point arithmetic as well as floating-point arithmetic , and have specific instructions to deal with complex filters and entropy coding. CSR produces the Quatro family of SoCs that contain one or more custom Imaging DSPs optimized for processing document image data for scanner and copier applications. Microchip Technology produces

819-643: The Fourier-transform or matrix operations. Some chips, like the Motorola MC68356, even included more than one processor core to work in parallel. Other DSPs from 1995 are the TI TMS320C541 or the TMS 320C80. The fourth generation is best characterized by the changes in the instruction set and the instruction encoding/decoding. SIMD extensions were added, and VLIW and the superscalar architecture appeared. As always,

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858-450: The PIC24 based dsPIC line of DSPs. Introduced in 2004, the dsPIC is designed for applications needing a true DSP as well as a true microcontroller , such as motor control and in power supplies. The dsPIC runs at up to 40MIPS, and has support for 16 bit fixed point MAC, bit reverse and modulo addressing, as well as DMA. Most DSPs use fixed-point arithmetic, because in real world signal processing

897-598: The RNC with Node B. And at last, there is the Iur interface, which is an internal interface most of the time but can exceptionally be an external interface too for some network architectures. The Iur connects two RNCs with each other. Node B Node B corresponds to BTS ( base transceiver station ) in GSM . This is the hardware that is connected to the mobile phone network that communicates directly with mobile handsets. In contrast with GSM base stations, Node B uses WCDMA / TD-SCDMA as

936-406: The additional range provided by floating point is not needed, and there is a large speed benefit and cost benefit due to reduced hardware complexity. Floating point DSPs may be invaluable in applications where a wide dynamic range is required. Product developers might also use floating point DSPs to reduce the cost and complexity of software development in exchange for more expensive hardware, since it

975-600: The air interface technology. As in all cellular systems, such as UMTS and GSM , the Node B contains radio frequency transmitter(s) and the receiver(s) used to communicate directly with mobile devices, which move freely around it. In this type of cellular network, the mobile devices cannot communicate directly with each other but have to communicate with the NodeB. Traditionally, the Node Bs have minimum functionality, and are controlled by an RNC ( Radio Network Controller ). However, this

1014-497: The architectural optimizations. DSPs are usually optimized for streaming data and use special memory architectures that are able to fetch multiple data or instructions at the same time, such as the Harvard architecture or Modified von Neumann architecture , which use separate program and data memories (sometimes even concurrent access on multiple data buses). DSPs can sometimes rely on supporting code to know about cache hierarchies and

1053-409: The associated delays. This is a tradeoff that allows for better performance . In addition, extensive use of DMA is employed. DSPs frequently use multi-tasking operating systems, but have no support for virtual memory or memory protection. Operating systems that use virtual memory require more time for context switching among processes , which increases latency. In 1976, Richard Wiggins proposed

1092-414: The clock-speeds have increased; a 3 ns MAC now became possible. Modern signal processors yield greater performance; this is due in part to both technological and architectural advancements like lower design rules, fast-access two-level cache, (E) DMA circuitry, and a wider bus system. Not all DSPs provide the same speed and many kinds of signal processors exist, each one of them being better suited for

1131-591: The equivalent GSM network. Unlike in GSM, the cells' size is not constant (a phenomenon known as " cell breathing "). This requires a larger number of Node Bs and careful planning in 3G ( UMTS ) networks. Power requirements on Node Bs and user equipment (UE) are much lower. It is connected to RNC of UMTS network through IUB interface. A full cell site has a cabinet, an antenna mast and actual antenna. An equipment cabinet contains e.g. RF power amplifiers , digital signal processors and backup batteries . What you can see by

1170-638: The family offering dual or quad 16-bit MACs. The CEVA-XC DSP family targets Software-defined Radio (SDR) modem designs and leverages a unique combination of VLIW and Vector architectures with 32 16-bit MACs. Analog Devices produce the SHARC -based DSP and range in performance from 66 MHz/198 MFLOPS (million floating-point operations per second) to 400 MHz/2400 MFLOPS. Some models support multiple multipliers and ALUs , SIMD instructions and audio processing-specific components and peripherals. The Blackfin family of embedded digital signal processors combine

1209-425: The features of a DSP with those of a general use processor. As a result, these processors can run simple operating systems like μCLinux , velocity and Nucleus RTOS while operating on real-time data. The SHARC-based ADSP-210xx provides both delayed branches and non-delayed branches. NXP Semiconductors produce DSPs based on TriMedia VLIW technology, optimized for audio and video processing. In some products

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1248-466: The gap between conventional micro-controllers and FPGAs CEVA, Inc. produces and licenses three distinct families of DSPs. Perhaps the best known and most widely deployed is the CEVA-TeakLite DSP family, a classic memory-based architecture, with 16-bit or 32-bit word-widths and single or dual MACs . The CEVA-X DSP family offers a combination of VLIW and SIMD architectures, with different members of

1287-507: The market. In 1980, the first stand-alone, complete DSPs – Nippon Electric Corporation 's NEC μPD7720 based on the modified Harvard architecture and AT&T 's DSP1 – were presented at the International Solid-State Circuits Conference '80. Both processors were inspired by the research in public switched telephone network (PSTN) telecommunications . The μPD7720, introduced for voiceband applications,

1326-414: The same time. Digital signal processing (DSP) algorithms typically require a large number of mathematical operations to be performed quickly and repeatedly on a series of data samples. Signals (perhaps from audio or video sensors) are constantly converted from analog to digital, manipulated digitally, and then converted back to analog form. Many DSP applications have constraints on latency ; that is, for

1365-526: The satellites' weight, power consumption, complexity/cost of construction, reliability and flexibility of operation. For example, the SES-12 and SES-14 satellites from operator SES launched in 2018, were both built by Airbus Defence and Space with 25% of capacity using DSP. The architecture of a DSP is optimized specifically for digital signal processing. Most also support some of the features of an applications processor or microcontroller, since signal processing

1404-478: The side of a road or in a city center is just an antenna. However, the tendency nowadays is to camouflage the antenna (paint it the color of the building or put it into an RF-transparent enclosure). Smaller indoor nodes may have an antenna built into the cabinet door. A Node B can serve several cells, also called sectors, depending on the configuration and type of antenna. Common configuration include omni cell (360°), 3 sectors (3×120°) or 6 sectors (60 degree each, not

1443-402: The system to work, the DSP operation must be completed within some fixed time, and deferred (or batch) processing is not viable. Most general-purpose microprocessors and operating systems can execute DSP algorithms successfully, but are not suitable for use in portable devices such as mobile phones and PDAs because of power efficiency constraints. A specialized DSP, however, will tend to provide

1482-509: Was made possible with a 7 μm PMOS fabrication process . In 1978, American Microsystems (AMI) released the S2811. The AMI S2811 "signal processing peripheral", like many later DSPs, has a hardware multiplier that enables it to do multiply–accumulate operation in a single instruction. The S2281 was the first integrated circuit chip specifically designed as a DSP, and fabricated using vertical metal oxide semiconductor ( VMOS , V-groove MOS),

1521-505: Was one of the most commercially successful early DSPs. The Altamira DX-1 was another early DSP, utilizing quad integer pipelines with delayed branches and branch prediction. Another DSP produced by Texas Instruments (TI), the TMS32010 presented in 1983, proved to be an even bigger success. It was based on the Harvard architecture, and so had separate instruction and data memory. It already had

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