ncar & nextel - nets web · history of mobile telephone service (cont) • 1970 fcc requests...
TRANSCRIPT
Covered Today
• History of Mobile Communication• Cellular at NCAR• Current Issues• Future Possibilities
History of Mobile Telephone Service
• 1946 Mobile Telephone Service introduced (MTS).
• 1947 First concept design of cellular in by AT&T• 1958 & 1968 AT&T petitioned for frequencies in
the 800MHz and up bands.• 1964 IMTS was introduced.• 1969 AT&T built a one dimensional cell system.
History of Mobile Telephone Service (Cont)
• 1970 FCC requests AT&T to build first cellular mobile vehicle prototype system for allocation bandwidth justification.
• 1973 Motorola demonstrated first portable mobile phone handset.
• 1982 AT&T is notified by justice department to split apart.
• 1983 FCC completes spectrum allocation for cellular 800Mhz A&B bands.
History of Mobile Telephone Service (Cont)
• 1983 simultaneously AT&T and Motorola build first competing Advanced Mobile Phone Service (AMPS) cellular systems G1.
• 1984 AT&T relinquishes Bell System’s Wireless.• 1989 Time Division Multiple access TDMA
introduced.• 1995 Code Division Multiple access CDMA
introduced.• 1996 Nokia introduces first handheld
Phone/Computer.
NETS: Cellular Transition
• Early methods– Pager coverage/response issues– Bulky licensed radio’s
• Cellular’s attractive features– Nation wide mobile phone access– Push to Talk (PTT) – Data features
Adopted Nextel Solution• Nextel pluses
– Unique PTT feature handy– Good nationwide major Metropolitan coverage
• Nextel shortfalls – Internal building coverage– Nationwide coverage inconsistent– Rural coverage – Lack of roaming
Nextel ML Building Coverage Solution
• Approached Nextel directly.– Nextel did ML Site evaluation.– Nextel Solution costly.– Acquired Nextel Design Implementation
• Evaluated Nextel Solution– Acquired few basic system components.– Evaluated components – Acquire & Install Phase 1 products– Acquire & Install Phase 2 products– Expand coverage areas
New Nextel SMR800 System
• Systems Specifications– SMR800 Single Band limited
• Repeaters• Antenna
– Open Band components limits• Combiner/dividers .8-2.3GHz• Directional Couplers .8-2.3GHz• Lightning Protector .7-2.7GHz• Cabling .03-5.8GHz
Nextel Network Testing
• Spectrum Analyzer• iDEN internal handset diagnostic mode.
– Diagnostic Access code i836 Keys:• Press #Key,*Key, Menu Key, and Right Arrow Key
sequence in less than 5 seconds.• Phone will enter “Trace Mode” Menu• Two Operational Diagnostic modes
Additional Nextel Building Site Installations
• Design: Pseudo Complete– ML– FL4– FL3
• Design: Inherited Partial Installs– CG1– FL2
ML Nextel Building System Issues
• Ongoing – Building to system call handoffs– Difficult Coverage
• Small nodes• Exterior areas
• New – Nextel Frequency Re-band
• Building Network wide upgrade needed
– Nextel/Sprint Merger
Sprint/Nextel Merger
• Sprint acquired Nextel– Two different Technologies– Two different Bands
• Nextel’s future?– Frequency band
NCAR Cellular Solutions
• Correct Nextel Issues• Correct Nextel Issues & Install Second
Vendor Solution• Abandon Nextel & Install New Vendor
Solution– Cellular– VOIP/Cellular
Upgrade Present System
• Pro’s– Existing Nextel users
not displaced– SMR 900 dead air &
drop calls will be eliminated.
• Con’s– Complete System
replacement, minus media, costly.
– Live with present system pitfalls
– Nextel uncertain future
Correct Nextel Issues & Install Second Vendor Solution
• Pro’s – Dual system
redundancy/options– Existing Nextel users
not displaced– Overcome Nextel
Nationwide short falls
• Con’s– Complete Nextel
System overhaul minus media replacement costly
– Complete Second System Installation required.
– Possibility of Dual System Interference
– Nextel uncertain future
Abandon Nextel & After Installation of a New Vendor Solution
• Pro’s– Overcome Nextel
Nationwide short falls– No further investment
in present systems.
• Con’s– All UCAR users will
need to buy in.– New system
technology and installation costs an unknown at this time.
New FCC Public Safety Building Coverage Issues
• Public Safety – First Responder Communications
• 200 Cities have already adopted.
• Present SMR800 system partially accommodates Public Safety.– Future may include 700MHz.
FCC & Cellular Vendor Concerns over in Building Repeaters
• FCC – Interference
• Vendor– Interference– Experienced personnel– Maintained
American Signal Multiplexing Methods
• TDMA is TDM based• GSM is TDM based• iDEN Nextel is TDM based • CDMA by Qualcomm Technologies
Wireless Voice: The Skies the limit
• Conclusion:– Knowns
• We need to define what are OUR requirements are!– Voice
» In Building!» Nation Wide!» Rural!» PTT?
– Data?
Wireless Voice: The Skies the limit (Cont)
• Conclusions:– Unknowns
• Selected systems technology• Selected systems band • Selected system longevity• Selected systems shortfalls