Plainview, New YorkTest instrumentation house Aeroflex announces the availability of a TETRA Direct Mode option for its existing 3900 Series test platform (shown above). TETRA (TErrestrial Trunked RAdio) is based on digital PMR (Private Mobile Radio) and PAMR (Public Access Mobile Radio) technology.
TETRA is used for police, ambulance, and fire services, security services, utilities, military, public access, fleet management, transport services, closed user groups, factory site services, and mining applications, to name a few.
With support of ETSI (European Telecommunications Standards Institute), the TETRA standard is used throughout Europe. The standard builds upon analog trunked radio systems and GSM cellphone technologies.
Direct Mode operation is between radios, packet data, and circuit data transfer services. TETRA uses TDMA (Time Division Multiple Access) with four user-channels on one radio carrier and 25-kHz spacing between carriers.
The 3900 Series digital radio test platform comprises an RF receiver and signal generator, as well as DSP-powered sub-systems. Running instrument applications software, the 3900 Series is deemed to be a future-proof modular design that's software re-configurable. One test set in the series covers a frequency range up to 1-GHz. Another expands the operating range to 2.7-GHz. These test sets are priced from about $28,000 to $30,000.
The new option, priced at about $2700, gives a 3900 comprehensive direct mode call setup and parametric testing capabilities. Complementing a TETRA MS Trunked Mode option, the Direct Mode option gives test coverage of a radio's hardware and signaling in areas that have additional demands placed upon them due to the technical differences between Direct and Trunked modes of operation.
Call Set-up Signaling
The 3900 DM option offers protocol call setup signaling capability, confirming a radio's ability to accept and differentiate between different call types. The option also provides talk back, test tone, and silence capability. That enables receiver and audio functions to be checked while in Direct Mode.
With the DM option, burst type selection has also been expanded. The option provides handling for the initial continuous transmissions that occur in Direct Mode.
The parametric functions with the TETRA Direct Mode option include burst type selection, measurement of power and power profile (taking account of continuous and discontinuous bursts), and measurement of frequency error, vector error (RMS, peak, residual carrier), and timing error. The option also gives you a graphical display, such as constellation and phase trajectory displays.
The 3900 also provides call status/protocol history and information displays, and call set-up info (mobile or test-set originated group/open group [broadcast]/private call [including presence check]/emergency calls. The system also provides for talk-back, silence, and test tones for receiver and audio evaluation.
The system also supports mobile/test-set transmit request, and mobile/test-set end-of-transmission features. Test-set timers are available for test-set transmit time, quiet time before test-set transmission, and quiet time before implicit clear down (reservation time). You also get explicit call clear-down from mobile/test-set or implicit clear-down on mobile/test-set quiet time expiry.
Price And Availability
Aeroflex says its test sets TETRA options are "competitively priced against current offerings." Delivery is about eight weeks.
Click here for access to a 3900 Series datasheet (in Adobe Acrobat .PDF format).
For more info, contact Shawn Driskill at Aeroflex Inc., 35 So. Service Rd., Plainview, New York 11803. Phone: 316-529-5384 or 516-694-6700. Fax: 516-694-4823.
Aeroflex, 516-694-6700, www.aeroflex.com