The unprecedented growth in the Bluetooth standard has led to a great demand for tools to perform design/development, pre-certification, conformance, and manufacturing testing. An assortment of specialized test equipment now offered by the leading manufacturers provides testing solutions for the entire product cycle. Also, there is a demand for tools because every product must pass the Bluetooth qualification tests before it can be sold. These tools, therefore, play a major role in preparing for the mandatory conformance tests.
Bluetooth is a wireless communications standard for seamlessly connecting notebook computers, cellular phones, PDAs, and other portable handheld devices (see "A Low-Power, Frequency-Hopping System" p. 98). Due to its low cost, small form factor, and low power, it's rapidly gaining momentum and is poised to become the leading wireless communication technology for small mobile devices. It's backed by giant companies, such as Ericsson, IBM, Intel, Lucent, Microsoft, Motorola, Nokia, and Toshiba—the initial promoters of the Bluetooth Special Interest Group (SIG).
According to Allied Business Intelligence (ABI), annual shipments of Bluetooth-enabled devices will reach a whopping 1.4 billion units in 2005. That's more than a 25-fold increase in shipments from 53 million units this year.
The "Bluetooth" name actually dates back to the 10th century Danish king, Harald Blatand (or "Bluetooth" in English), who was credited with the unification of Denmark and Norway. Little did he know that 10 centuries later, a new technology representing the unification of the telecommunication and computer industries would be named in his honor. This multifaceted, emerging technology poses many design challenges ranging from analog RF to digital to protocol analysis. These are recognized by the leading manufacturers of test and design tools, and these companies are now offering a broad range of equipment that addresses the development, characterization, and verification of the Bluetooth components and products.
The most fundamental tool, the oscilloscope, requires good performance in bandwidth, input sensitivity, and sample rate for Bluetooth design and troubleshooting applications. Tektronix's TDS 3000 series of digital phosphor oscilloscopes can be used here. Suitable for Bluetooth development, they feature bandwidths of up to 500 MHz and sample rates of up to 5 Gsamples/s.
Additionally, the TDS 3000 family offers an impressive variety of acquisition modes and trigger types that are critical to accurate measurement and analysis. For example, the peak detect acquisition mode is used for capturing high-frequency and random glitches as narrow as 1 ns. The trigger system supports different trigger modes, including edge, logic, and pulse triggers. A waveform-processing feature allows channel-to-channel deskewing of ±10 ns for better timing measurement and accurate math waveforms. It also permits the addition, subtraction, multiplication, and division of waveforms.
Similarly, the 54620 series of mixed-signal oscilloscopes from Agilent Technologies is optimized for the verification and debugging of Bluetooth baseband signals. These combine the detailed signal analysis of an oscilloscope with the multichannel timing measurements of a logic analyzer, permitting simultaneous testing and monitoring of the high-speed digital signals and lower-speed analog signals.
Designers of mixers, oscillators, modulators, amplifiers, and other components frequently need to provide stimuli to the device under test (DUT) prior to the availability of a Bluetooth component in their system. Correct modulation, burst-profile, test-data sequences, hopping characteristics, and spectral shapes are necessary to determine performance under real-world conditions. For receiver designers, extremely accurate low-level outputs of test signals are required to test sensitivity. They're needed to test receiver performance in the presence of both modulated and carrier wave interfering carriers, too.
Tektronix's SMIQ series of signal generators and AMIQ arbitrary waveform generators were designed for such tasks. They feature 14-bit resolution, a 4 million sample memory depth, a 100-MHz sample rate, calculation of digitally modulated I/Q and IF signals, and superposition/simulation of impairments, as well as single-carrier, multicarrier, and CDMA signals.
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