Ideal for wireless design, research and development and production test engineers, the Aeroflex 3280 series of spectrum analysers offer digital demodulation for the analysis of 802.11a, b and g wireless networks. Digital demodulation in the 3280 Series spectrum analysers allows engineers to analyse the transmitter characteristics of a wireless device.

Digital demodulation in the 3280 Series is easily operated in one of two modes.

Full-frequency mode links the rear panel IF output at 421.4MHz to the demodulator input, allowing the user to demodulate signals over the full frequency range of the spectrum analyser (3GHz, 13.2GHz or 26.5GHz).

Dual-channel mode links directly from the instrument’s front panel or optionally via a rear panel connector to create a unique dual-channel instrument.

The frequency range for the direct input of the demodulator is 300MHz to 3GHz.

Although the 3280 Series’ digital demodulation hardware option does not include direct IandQ outputs, users who require it can access a direct digital IandQ output in streaming serial format by adding the optional low-voltage data signal (LVDS) output cable.

Digital demodulation in the 3280 Series is easily operated in one of two modes.

Full-frequency mode links the rear panel IF output at 421.4MHz to the demodulator input, allowing the user to demodulate signals over the full frequency range of the spectrum analyser (3GHz, 13.2GHz or 26.5GHz).

Dual-channel mode links directly from the instrument’s front panel or optionally via a rear panel connector to create a unique dual-channel instrument.

The frequency range for the direct input of the demodulator is 300MHz to 3GHz.

Although the 3280 Series’ digital demodulation hardware option does not include direct IandQ outputs, users who require it can access a direct digital IandQ output in streaming serial format by adding the optional low-voltage data signal (LVDS) output cable.

Start with the news release Centralised Ethernet system made for automation from Micromech, which we summarised at the time by saying “A high-speed, digital motion-bus solution connects a motion controller to multiple drives and I/O points using standard Ethernet networking hardware”. A couple of weeks before, we featured the news release Ethernet migrates into automation I/O level from ARC Advisory Group: “The worldwide market for Ethernet-based devices and I/O is expected to grow at a compounded annual growth rate of 27.5% over the next five years”.

In January 2008, we covered the news from Block UK concerning its Harmonic filter modules - take a look at Reduce harmonics in the power supply, save costs.

Demodulation frequency bandwidth (-3dB) of 120MHz, and input frequency ranges of 220MHz to 3.2GHz, and 4.96 to 6.2GHz, with 0.1Hz resolution.

Optional high-speed digitisers are available together with generation and analysis software for EVM (error vector magnitude) and BER (bit error rate) measurements.

Transmitter and receiver testing can be carried out for the IEEE802.11a, Hiperlan/2 (OFDM) and IEEE802.11b (CCK) standards.

The instrument features RS232 and GPIB interfaces, and a sampling clock generation function is available as an option.

Rohde and Schwarz has extended the demodulation bandwidth of its R and S FSQ high-end spectrum analyser

With the expanded R and S FSQ-B72 option, the instrument now offers 120MHz over the entire frequency range - which extends up to 3.6, 8, 26.5 or 40GHz, depending on the model. In addition to its large bandwidth, the R and S FSQ with the R and S FSQ-B72 option has a very high dynamic range of 70dB.

In combination with the instrument’s high measurement quality, the enhancement makes the R and S FSQ the ideal choice for all broadband applications - including the development and production of amplifiers for UMTS or WiMAX, the analysis of satellite signals or measurements on the 802.11n and 802.16 broadband standards.

The device is compliant with DVB-C as well as ITU-J.83 annex A and C standards, and supports direct IF sampling with a variable frequency of up to 60MHz. It also includes a full QAM demodulation path including a 10bit A/D function and has been designed to work in 256 QAM on extremely noisy and distorted channels.

Capable of providing a fast acquisition time for QAM signals of less than 20ms, the device interfaces gluelessly to all leading MPEG decoders currently on the market, and supports variable demodulation symbol rates between 7 and 0.7Mbaud/s. It only requires a single 8MHz SAW filter and can be used even in environments where extreme adjacent interference is prevalent.

All MB87L2070s will be supplied with a full analogue front-end reference design which offers a quick and cost-effective system integration path and supports multiple types of tuners.

The new products, sampling now and available for mass production in Q1′2007, include the AU8521 optimized for PC-TV applications, the AU8522 targeted at dual ATSC/NTSC systems, the AU8523 cost-optimized for systems with external analog decoders, and the AU8524 cost-optimized for digital only receivers. All employ Auvitek’s patent-pending FADE(TM) (Fully Adaptive Demodulation and Equalization) technology to deliver optimal performance across the continuum of infinitely diverse signal conditions existing today. Building on the recognized performance of the earlier AU850x family, released these new ICs were recently described by the CRC, an independent DTV testing authority, as achieving “the longest echo span that CRC have tested.”

For PC applications, Auvitek provides reference designs, software and WHQL and/or Vista certified drivers which are all available now. For CE applications, Auvitek offers a complete software driver suite as well as development boards and reference designs.

Auvitek President and CEO Peter Birch noted: “Demodulator Performance can make or break the customer experience in DTV. The AU852x family of ICs follows the Auvitek philosophy of delivering optimized solutions that allow customers to maximize their enjoyment of the exciting display technologies available both today and in the future.”

In addition to extremely low power, the 852x family offers full compliance with the ATSC A/74 recommendations for digital TV receiver performance metrics. The 852x products provide outstanding performance not only in the lab but also in the infinitely diverse range of real world reception conditions making this family the leading VSB solutions on the market.

AU852x performance will be demonstrated at the 2007 Consumer Electronics Show (CES) in the Sands Hotel at Auvitek’s Booths 68341 and 68342. Additional information is available at www.auvitek.com.

ABOUT AUVITEK

Auvitek International Ltd. is a leading fabless semiconductor company focused on developing ICs for the worldwide Digital Television and Multimedia Convergence markets. With US operations based in Silicon Valley, Auvitek has development sales, and support offices in Shanghai, Shenzhen, Hong Kong, and Taipei. Auvitek recently launched its latest generation of DTV/HDTV demodulation processors. Based on patent pending FADE(TM) (Fully Adaptive Demodulation and Equalization) technology, and combined with extremely efficient and unique algorithms, these products offer the highest performance demodulation solutions in the industry. This leading edge technology is helping Auvitek revolutionize DTV design by delivering crystal clear video and audio to the consumer electronics and personal computer markets. Auvitek is backed by leading investors including Bank of America Ventures, KLM Capital Group, Storm Ventures, and VenGlobal Capital.

The DVB-H demodulator / decoder is available in the form of a system implementation in RTL and enables TV reception on next-generation handheld devices. It supports a variety of low IF and zero IF front-end tuner architectures and provides standard MPEG transport stream and IP data stream outputs.

The DVB-H design, which builds on a DVB-T demodulator/decoder, supports both DVB-H and DVB-T receiver functionality, enabling devices to be targeted at both markets.

Micronas today announced availability of its highly-anticipated DRX-H family of multi-standard 8VSB/QAM/QPSK/NTSC demodulator products targeting applications in Digital TV-sets, set-top boxes, multimedia-PCs, DVD recorders, PVRs and tuner modules. The feature-rich DRX-H product family delivers superior performance and ATSC compliance in US Digital Television (DTV) applications, while enabling compliance with the “FCC Tuner Mandate”. Under the FCC order, TV manufacturers are required to integrate digital receivers into televisions and certain other consumer electronics devices by certain deadlines.

Based on Micronas’ proprietary primeD technology, the DRX-H provides a superior solution to satisfy the increasing market demand for more robust and higher quality DTV reception performance. Signal reflections, commonly referred to as echoes or ghosts create significant reception problems for DTV systems by introducing a time-delayed but otherwise identical signal to the receiver. Echoes can be caused by any obstruction in the signal path like the shape of the terrain, buildings, cars, even airplanes, and are especially prevalent in urban environments. These echoes often reach or exceed the level of the desired signal (so-called 0dB echoes), disrupting reception with most of today’s solutions.

As opposed to merely filtering echoes out, primeD technology combines multiple echoes to create a single, stronger signal, resulting in enhanced overall reception quality. Devices employing DRX-H are able to cope with notoriously difficult terrestrial reception situations and provide measurable improvements to the overall DTV experience of consumers. The performance benefits of DRX-H compared with other available solutions are supported by lab and field tests conducted by independent test facilities.

“primeD is based on design work undertaken by a team of US DTV experts, who came to Micronas as part of its May, 2004 acquisition of LINX Electronics, a leader in 8VSB demodulator design” according to Hans-Juergen Desor, Vice President Consumer Products at Micronas. “The LINX acquisition combines LINX DTV expertise with Micronas DVB technology to create a single-chip solution for digital TV”.

“Unlike most competitors’ implementations, Micronas’ DRX-H demodulator does not simply discard undesired echoes but combines them in a unique patented manner with the desired signal which results in superior performance under realistic field conditions. We are approaching theoretical limits of the 8VSB demodulation standard thanks to our unique implementation” said Rich Citta, Chief Scientist of Micronas Semiconductors, Inc., an industry veteran and one of the key architects of the current ATSC DTV standard.

Offering the highest level of integration and performance of any solution on the market today, the DRX-H integrates an ATSC A/53-compliant 8VSB demodulator with an ITU-T J.83 Annex B-compliant QAM demodulator, a high quality NTSC demodulator, and a BTSC decoder, as well as an OOB (Out of Band) QPSK demodulator and OOB Local Oscillator for seamless integration into DCR (Digital Cable Ready) television sets.

The DRX-H is optimized for applications ranging from flat panel HDTVs to highly space-constrained Integrated Tuner/Demodulator (IT/D) modules. All features of the DRX-H are controlled via a standard I[sup.2]C-interface. The DRX-H includes its own on-chip memory.

Micronas offers four versions of the DRX-H, with tailored functionality and corresponding ASP, in order to deliver the best cost versus feature ratio for different market applications. All are available in a 14×20mm 128 pin QFP package.

The DRX-H solution includes a range of software modules to control the device. All modules share a common API. This allows customers to complete their design and get to production quickly.

“The transition to digital television reception presents new design challenges to our customers. We are committed to supporting them with our DRX-H turnkey solution which will result in improved time to market and superior receiver performance without compromises” said Stefan Szasz, Marketing Manager ATSC at Micronas Semiconductors Inc., San Diego, California.

VECTOR MODULATION INSTRUMENTS such as the HP 8780A Vector Signal Generator and the HP 8980A Vector Analyzer provide a test system for measurement applications in such fields as digital microwave radio, communications, and radar. Some of the technologically new developments in this series of products are the modulation capabilities (complex, wideband signals), the high-resolution CRT display, and the 350-MHz bandwidth.

Statistics in Calibration Routines

Calibration consists of comparing a set of measurements from an uncharacterized instrument (e.g., an HP 8981A) with a defined reference standard (e.g., an HP 8780A) according to a measurement algorithm. Thus the calibration model relates the observed measurement readings to the reference standard. A model is never perfect, and the difference between the model and reality can be characterized according to two types of errors that may be present:

* Systematic errors resulting from incomplete specification of the calibration model

* Random errors, or small, unpredictable fluctuations that affect every measurement but are themselves unmeasureable.

Statistical methods can be used to address both types of errors. First, the calibration should be designed to allow identification of possible systematic departures between the model for measurement and the observed data. Second, the influence of random errors can be assessed when estimating the parameters in the model that relate to the measurement process and their uncertainties. In this paper, we shall assume that the random errors are independent and identically distributed according to a symmetric distribution; that is, that the individual errors cannot be predicted in either size or direction, and that the chances of an erroneous measurement being too large or too small are roughly equal. (Diagnostic tools for checking the validity of these assumptions and the consequences of their violation are discussed in connection with the examples later in this paper.)

Rarely is a single estimate of a target quantity sufficient. For example, reporting a sample mean without its standard error provides no information on the reliability of the data that went into that sample mean. The same is true for estimates of the parameters describing the measurement process. These estimates are the calibration factors, and certain limits of fluctuation may be desirable (e.g., gain adjustment accurate within 1%). Therefore, an important part of the statistics in a calibration algorithm is the derivation of associated measures of uncertainty for the calibration factors.