Design Article
Selecting a handheld RF analyzer for tough conditions
Wilkie Yu, Agilent Technologies
11/12/2012 8:53 AM EST
Title-1
Defining field-ready ergonomics
Time spent in the field made indelible impressions that led to practical, meaningful decisions about ergonomics. For example, a nonslip rubber grip—built into the case—that fits securely into the user’s hands can also be designed to prevent the analyzer from sliding off the hood of a vehicle.
A vertical or “portrait” orientation would make an instrument easy to hold. Coupling that with a carefully designed keypad layout will make it easy for a user to operate the instrument with thumbs (see Figure 3). Also, a weight of about 3.0 kg (about 6.6 lbs) is relatively easy to carry for extended periods in the field.
Because the instrument may be used day or night, inside or outside, the user will benefit from a bright, low-reflective display and multiple display modes that optimize viewing under a wide range of lighting conditions. In addition, backlit keys will enable operation in darkness.
Reducing power consumption
The electronic design of a handheld analyzer requires a complex balance between performance, power consumption, heat, and battery life. For Agilent’s FieldFox, in-house scientists modified existing high-performance chips and technologies to retain performance while reducing power consumption. The result: an analyzer that draws about 14 W and lasts 3.5 hours on a single charge. Because the electronics consume only 14 W of power, the enclosure can be completely sealed. The power-efficient design has another benefit: the instrument provides fully specified performance over an operating temperature range of 14 to 131 °F (-10 to +55 °C).
Leveraging benchtop capabilities
For the Agilent team, the next step was to pack the required levels of performance and capability into a rugged, ergonomic design that met the criteria described above. As a starting point, they borrowed capabilities from Agilent’s benchtop analyzers.
For network analysis, the designers leveraged built-in calibration hardware and calibration algorithms from high-end vector network analyzers (VNAs) to enable precise, repeatable measurements. With an emphasis on portability, the designers simplified calibration by adding built-in standards, a choice that enables measurements in the field without additional accessories. With most other instruments, the addition of devices such as jumper cables to the test port requires recalibration using an external calibration kit that must be carried into the field.
To enhance spectrum analysis, the design team leveraged the power measurements used in Agilent benchtop signal analyzers. This enables one-button power measurements of channelized communication systems. For improved accuracy, the designers created an internal amplitude alignment function that operates automatically as environmental conditions change. This provides amplitude accuracy of ±0.5 dB with no warm up required across an operating temperature range of 14 to 131 °F.
Covering more ground
The results of this process are the Agilent FieldFox handheld analyzers (see Figure 4). A FieldFox analyzer can be configured as a cable and antenna tester (CAT), spectrum analyzer or vector network analyzer. Additional capabilities include a power meter, a vector voltmeter, an independent signal source, a variable DC supply, a frequency counter, an interference analyzer, and built-in GPS. The FieldFox family consists of 16 models, with top-end frequencies of 4, 6 and 6.5 GHz in the RF models and 9, 14, 18 and 26.5 GHz in the microwave models.
This level of flexibility can replace a variety of instruments. It also enables a user to define a “just right” initial configuration and, later on, easily amend it with additional capabilities as needs change and budgets allow. Because those capabilities are inclusive, a CAT version can be enhanced with any of the other capabilities—spectrum analysis, network analysis, etc.—by simply acquiring and applying a license key. No additional hardware is required, nor is a return to the factory.
As a final point, the product warranty is an important consideration for any instrument that will be used in the field. While most instruments have a one-year warranty, FieldFox handheld analyzers carry a three-year warranty.
For more information on FieldFox Analyzers from Agilent, see the review on Test&Measurement World.
For video demonstrations, head here.
If you liked this feature, and would like to see a weekly collection of related features delivered directly to your inbox, sign up for Test&Measurement World (www.tmworld.com) newsletters here
About the Author
Wilkie Yu is the worldwide marketing manager for Agilent Technologies’ RF and microwave handheld analyzers. Prior to this role, he was product manager for Agilent’s PXA and X-Series signal analyzers as well as the Asia business development manager for signal sources. Wilkie also spent time in China as the market development manager and helped build the local marketing organization. Wilkie earned his bachelor of science degree in electrical engineering and computer science from the University of California, Berkeley.
Defining field-ready ergonomics
Time spent in the field made indelible impressions that led to practical, meaningful decisions about ergonomics. For example, a nonslip rubber grip—built into the case—that fits securely into the user’s hands can also be designed to prevent the analyzer from sliding off the hood of a vehicle.
Figure 3: A portrait orientation coupled with sufficiently large front-panel buttons enables easy operation, even when wearing gloves.
A vertical or “portrait” orientation would make an instrument easy to hold. Coupling that with a carefully designed keypad layout will make it easy for a user to operate the instrument with thumbs (see Figure 3). Also, a weight of about 3.0 kg (about 6.6 lbs) is relatively easy to carry for extended periods in the field.
Because the instrument may be used day or night, inside or outside, the user will benefit from a bright, low-reflective display and multiple display modes that optimize viewing under a wide range of lighting conditions. In addition, backlit keys will enable operation in darkness.
Reducing power consumption
The electronic design of a handheld analyzer requires a complex balance between performance, power consumption, heat, and battery life. For Agilent’s FieldFox, in-house scientists modified existing high-performance chips and technologies to retain performance while reducing power consumption. The result: an analyzer that draws about 14 W and lasts 3.5 hours on a single charge. Because the electronics consume only 14 W of power, the enclosure can be completely sealed. The power-efficient design has another benefit: the instrument provides fully specified performance over an operating temperature range of 14 to 131 °F (-10 to +55 °C).
Leveraging benchtop capabilities
For the Agilent team, the next step was to pack the required levels of performance and capability into a rugged, ergonomic design that met the criteria described above. As a starting point, they borrowed capabilities from Agilent’s benchtop analyzers.
For network analysis, the designers leveraged built-in calibration hardware and calibration algorithms from high-end vector network analyzers (VNAs) to enable precise, repeatable measurements. With an emphasis on portability, the designers simplified calibration by adding built-in standards, a choice that enables measurements in the field without additional accessories. With most other instruments, the addition of devices such as jumper cables to the test port requires recalibration using an external calibration kit that must be carried into the field.
To enhance spectrum analysis, the design team leveraged the power measurements used in Agilent benchtop signal analyzers. This enables one-button power measurements of channelized communication systems. For improved accuracy, the designers created an internal amplitude alignment function that operates automatically as environmental conditions change. This provides amplitude accuracy of ±0.5 dB with no warm up required across an operating temperature range of 14 to 131 °F.
Covering more ground
The results of this process are the Agilent FieldFox handheld analyzers (see Figure 4). A FieldFox analyzer can be configured as a cable and antenna tester (CAT), spectrum analyzer or vector network analyzer. Additional capabilities include a power meter, a vector voltmeter, an independent signal source, a variable DC supply, a frequency counter, an interference analyzer, and built-in GPS. The FieldFox family consists of 16 models, with top-end frequencies of 4, 6 and 6.5 GHz in the RF models and 9, 14, 18 and 26.5 GHz in the microwave models.
Figure 4: The FieldFox handheld analyzers are designed to reduce equipment costs while enhancing convenience and efficiency.
This level of flexibility can replace a variety of instruments. It also enables a user to define a “just right” initial configuration and, later on, easily amend it with additional capabilities as needs change and budgets allow. Because those capabilities are inclusive, a CAT version can be enhanced with any of the other capabilities—spectrum analysis, network analysis, etc.—by simply acquiring and applying a license key. No additional hardware is required, nor is a return to the factory.
As a final point, the product warranty is an important consideration for any instrument that will be used in the field. While most instruments have a one-year warranty, FieldFox handheld analyzers carry a three-year warranty.
For more information on FieldFox Analyzers from Agilent, see the review on Test&Measurement World.
For video demonstrations, head here.
If you liked this feature, and would like to see a weekly collection of related features delivered directly to your inbox, sign up for Test&Measurement World (www.tmworld.com) newsletters here
About the Author
Wilkie Yu is the worldwide marketing manager for Agilent Technologies’ RF and microwave handheld analyzers. Prior to this role, he was product manager for Agilent’s PXA and X-Series signal analyzers as well as the Asia business development manager for signal sources. Wilkie also spent time in China as the market development manager and helped build the local marketing organization. Wilkie earned his bachelor of science degree in electrical engineering and computer science from the University of California, Berkeley.
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