JPL's Wireless Communication Reference Website

Chapter: Network Concepts and Standards, Paging

ReFLEX Protocol Technology Enables Wireless Access to the World Wide Web

In August 1996 Motorola's Advanced Messaging Group (AMG) the two-way messaging application that allows users to navigate the Internet. Through successful demonstrations in five metropolitan areas (Boston, MA; Chicago, IL; Dallas/Fort Worth, TX; southern Florida, Washington, DC), Motorola has proven that Tango®, the world's first two-way high-speed wireless messaging device, is capable of originating queries and receiving information from the World Wide Web. Web information accessible today to Tango® users includes business news, airline flight information, weather and sports scores.

"This demonstration of Web connectivity is the result of Motorola's drive to show the two-way wireless messaging market the kinds of applications Tango® and the ReFLEX protocol can enable," said Mario Rivas, vice president and general manager of Motorola's Advanced Messaging Products Division. "Our ultimate goal is to energize application developers to create innovative two-way applications that will propel the market forward."

Motorola succeeded in linking the Tango® to the Web by utilizing a Web server, SkyTel's 2-Way service -- based on Motorola's ReFLEX two-way paging transport protocol -- and simple programming logic to compress the amount of data returned to the Tango®. The tools to build this and other types of applications exist today and can be developed into commercial products.

Also, Motorola's Messaging Systems Products Group (MSPG), in cooperation with the Personal Communications Industry Association (PCIA), made available the TDP (Telocator Data Paging) suite of protocols available free of charge to wireless application developers on the World Wide Web. The TDP protocol suite allows wireless product users to send files, pictures and two-way messages over one- and two-way paging networks. The protocol suite, in hypertext (HTML), Adobe Acrobat and Adobe PostScript formats, is currently available on PCIA's World Wide Web site at:

ReFLEX is a member of Motorola's FLEX family of high-speed paging protocols, created to ensure the growth of the wireless messaging industry. The FLEX protocol has been adopted by seven of the 10 largest international paging markets in the world, and is the de facto standard in high-speed paging technology.


General Information

Tango Receiver
Frequency Bands: 940 - 941
Channel Spacing: 25 kHz
Bit Rate: 6400 bps
Signaling: 4 level FSK at 6400 bps
Frequency Deviation: +/- 2400 Hz binary
+/- 800 Hz and +/- 2400 Hz for 4 level
Paging Sensitivity: 14 micro-V/m address only, best position (6400)
Image Rejection: 35 dB
Spurious Rejection: 40 dB
Selectivity: 60dB at +/- 50 kHz
Frequency Stability: 1 PPM from -10C to +50C (REF. at +25C)
Temp. Spec: -10 to +50 degrees C
Frequency: Synthesized
Spurious Emissions: 5 nW
1 MHz Blocking: 80dB
Tango Transmitter
Frequency Bands: 901 - 902
Channel Spacing: 12.5 kHz
Bit Rate: 9600 bps
Signaling: 4 level FSK at 9600 bps
Frequency Deviation: +/- 800 Hz and +/- 2400 Hz for 4 level
Emissions: meets Narrowband PCS FCC specs
Power Into Antenna: 1 W
Frequency Stability: 1 ppm
Frequency: Synthesized
Weight with Batt.-Belt Clip: 5.6 oz (grams)
Size: 3.5" x 2.4" x 1.12" (9.4 cu in)
Battery Life: Approx. 14 days, 5 pages per day and a collapse value of 3
Battery: One 1.5V AAA size alkaline
Alert Tone Loudness: 72 dB SPL at 30 cm
Alert Tone Duration: 12 sec +/- 0.5sec, unless manually reset
Alert Tone Frequency: 3200 Hz

JPL's Wireless Communication Reference Website © Jean-Paul M.G. Linnartz, 1993, 1995.