PrimeWave 2000™
 
System Summary  

 

  PrimeWave 2000™ is an extremely flexible and scaleable method of providing telephony and data services to homes and businesses without the need to extend copper wire to each subscriber.

 Advanced but well proven Synchronous Code Division Multiple Access (S-CDMA™) technologies allow efficient and cost effective use of the Radio Frequency (RF) spectrum.

All standard telephony devices, such as telephones, faxes, and modems may be connected to the PrimeWave 2000™ Customer Premises Equipment (CPE) using standard interfaces. Data interfaces include X.21 and ISDN. 

Multiple standard interfaces and protocols to the public switched telephony network (PSTN) are provided through the PrimeWave 2000™ Network Interface Unit (NIU). Telephony and data signals are transmitted to the Customer Premises Equipment through the PrimeWave 2000™ Radio Base Unit. Multiple options are available to tailor the system to urban, suburban and rural environments. 

The system is a highly cost effective means of rapidly providing telephone and data services to: 

-          developing countries with little telephony infrastructure,

-          fast growing countries that need to expand their telephone systems, and

-          developed countries wanting to increase competitive voice and data services. 

PrimeWave 2000 supports: 

-          Voice, fax and modem transmission

-          Data services to 128Kbps (X.21 interface)

-          Resistance to eavesdropping (secure communications)

-          Connection to all current PSTN standard interfaces

-          Highest WLL subscriber capacity available

-          Highest WLL transmission quality available   

 

Features 
Telephone interface supports all standard telephone instruments including phone, fax and modem.
Customer Premises  Equipment available in a variety of configurations including Single (1), Dual (2), Quad (4) and Octal (8) line telephone, X.21, ISDN and Payphone.
 Variable telephone line concentration from 1:1 up to 251.
 Intra-calling function available. Subscriber to subscriber calling within the CPE and independent of the       PSTN. 
Feature calling services available including conference calling, call forwarding, call waiting, call transfer, etc.. 
Multiple PSTN protocols supported including CAS, CCS, C7, V5.2 and R2.  
Multilevel PSTN protocols support emergency 999 (911), hospital, police and VIP services. 
        Extensive fraud and service theft prevention features. 
Billing services available.  
System Level Parameters

 

Method of Operation                                 Full duplex. Frequency pairs are used, one for the forward channel and the other for the reverse channel.  

CDMA Method                                          Direct sequence spread spectrum (DSSS), forward and reverse channels.

Spreading Rate                                           2.7 Mcps.  

Forward Error Correction                           Trellis coding and Viterbi decoding in both forward and reverse channels.  

Frequency plan                                           Four frequency bands currently supported: 
               
2.0 to 2.3 GHz as defined by ETSI DE/TM 04031                 2.1 to 2.3 GHz as defined by ITU-R F.283-5                 2.5 to 2.7 GHz as defined by ITU-R F.283-5                 3.4 to 3.6 GHz as defined by CEPT Rec.1403-E  

Frequency channels                                    In the current supported plans, each band is divided into 14MHz channel pairs. Each channel is divided into 4, 3.5 MHz sub channels.

Encryption                                  Forward and reverse channels.  
Voice and data signals: PN scrambling.
Control signals: authentication encrypted.  

Voice Compression                      Voice mode only: A-law companding with ADPCM. A-law only for fax and modem (ADPCM bypassed). For less bandwidth efficient cases, voice mode can be used with A-law only, and no ADPCM compression.  

Equipment Summary  

Customer Premises Equipment (CPE)  

Subscriber Unit (SU)                    One piece enclosure includes antenna, RF circuitry, modem, telephone interface and data interface.  

Network Termination Unit (NTU)    Provides the boundary between the telephone system equipment and customer’s equipment.

Uninterruptible Power Supply        Maintains power supply during mains power (UPS) failure.                                                        

  Central Site Equipment  

Radio Base Unit Antenna             Provides the aperture for transmission and reception of radio signals within one cell.

Radio Base Unit (RBU)                One rack of equipment that includes RF circuitry, modem, telephone interface and data interface.  

Network Interface Unit (NIU)          Provides the interface between the PSTN and the RBU, controls the PSTN protocols 

System Capacity (System = single NIU. Multiple NIUs can be supported)  

Active telephone lines per RBU     100 active lines, up to 119 under ideal conditions (Note: telephone lines can optionally be data connections).  

Maximum lines per RBU              Up to 2500 with 25:1 concentration.  

Maximum RBUs per NIU (system)  Up to 15 (assumes no NIU intra-calling. When intra-calling is used, more RBUs can be supported).  

Maximum active lines per NIU        Up to 1500. (system)  

Maximum lines per NIU (system)    10,000 lines.  

RBUs per cell                             Variable depending on antenna, frequency and PN code selection.  

Interfaces  

Network Interface Unit (NIU)  

PSTN Physical Interface              Twisted pair VF channel bank or E1 (75 or 120 Ohm). Up to 1500 ports.

PSTN Protocol Interface               Flexible to accommodate all known CAS, and CCS protocols.

RBU Interface                              1 to 4 E1 connections per RBU. The E1 signals can be relayed to accommodate remote RBUs. Up to 15 RBUs can be supported from a single NIU.  

Power Input                                 -48VDC.

 

Radio Base Unit (RBU)  

NIU Interface                               One to four E1 connections. The E1 signals can be relayed to accommodate remote RBUs.

Antenna                                      Coaxial cables of up to 100 metres connect to the antennas. For space diversity, up to two antennas can be connected. 

Power Input                                  24 VDC, 48VDC or 60VDC.  

 

Customer Premises Equipment

Telephone Interface                     One to eight telephone lines with independent telephone numbers using standard tip and ring signaling.  

Payphone                                   One or two payphones.  

X.21 Data Interface                      One or two standard DB15 connectors.  

Power Input                                Universal AC input.    

Antennas  

RBU Transmit and Receive Gain    8 dBi, max. Optional sectored antennas with increased gain 

SU Transmit and Receive Gain      18 dBi, max.

Polarization                                 Right Hand/Left Hand Circularly Polarized (RHCP/LHCP).  

Transceivers  

RBU Power Amplifier Output         +35 dBm nominal.    

SU Power Amplifier Output           +14 dBm nominal.  

Modulation.                                 Quadriphase shift key (QPSK) data modulation with BPSK    spreading.  

Demodulation                              Coherent.  

User Data Rate per SU                 Variable in real time to support single, dual and quad line configurations. 32Kbps, 64Kbps, 96Kbps and 128Kbps supported.  

Bit Error Rate (BER)                    < 10-6.  

Receiver Sensitivity                      -114 dBm.  

System Sensitivity                        -111 dBm (includes the effects of multi user interference).  

Power Control                              Reverse channel, 40 dB range.  

 

Radio Base Unit  

Reliability                                     25 years mean time to hardware stop. (MTTHS).  

Redundancy                                Option for N+1 redundancy on all major components to ensure continued operation in the presence of a failure.  

Space Diversity Option                 A second antenna can be added to improve performance in a multi-path environment through space diversity, when required.  

Maintainability                            All circuit cards are replaceable without interrupting system operation and with power in (Hot Swappable).  

Operating Environment                -10 to +55 C, indoor.  

Size                                            One standard rack, 483 mm (19 inch) wide, 1300 mm high (27U), 450 mm deep.  

Cooling                                       Forced air cooling.  

Customer Premises Equipment

Equipment Interfaces                   Subscriber Units can be configured to interface to the following:  
-          One to eight telephone lines  
-          Single or dual X.21 ports  
-          One or two payphones  
-          One telephone and one X.21 port
 

SU Reliability                             10 years mean time between failure (MTBF).  

SU and NTU Environment             -30 to +55 C, Outdoor. Environmentally sealed and UV resistant.  

Power Supply Environmental         -10 to +55 C, Indoor.  

SU Size                                       41cm x 41cm x 8cm (16 x 16 x 3 inches).  

NTU Size                                     12cm x 13cm x 6cm (4.75 x 5.25 x 2.5 inches).  

Power Supply Size                        19cm x 26cm x 12 cm (7.5 x 10 x 4.75 inches).  

Cooling                                          Natural convection only. 

 

Customer Premises Equipment  

Human Interface                          One computer terminal controls one NIU and all connected RBUs (up to 15).  

Provisioning                                The Control Terminal provides all necessary tools to provision the system, including adding, reconfiguring and deleting users.  

Monitoring                                   The Control Terminal allows monitoring of a wide variety of system parameters. System health and status including data link quality, are recorded in each RBU every 10 minutes and can be maintained for up to 48 hours. This data can be downloaded to the Control Terminal.  

Fault detection and Isolation         Full set of built in tests provided to isolate failures to the circuit board on which they occur. All faults and performance degradations are reported to the Control Terminal. System tests, element tests and circuit board self tests are provided. Tests are conducted automatically but can also be initiated from the Control Terminal.  

Phone Tests                                Make/Break dial tone and loop back test capability is provided.  

Maintenance                               All equipment is designed for ease of maintenance. RBU can be maintained without interrupting service.  

Billing                                         Full billing data is available.  

Unintended System Use              Extensive provisions to detect and defeat CPE equipment theft, service pirating, intrusion etc..  

Software Uprgades                      Upgrades can be down loaded to the NIU, RBU and SU from the Control Terminal. SU downloads software over the air via the forward channel.  

TMN                                          Growth path to TMN services, including Q interfaces.  

 

What is Spectral Efficiency?  

Spectral efficiency is a measure of how effectively a system makes use of a limited amount of Radio Frequency spectrum!!!  

It is calculated as:  

AVAILABLE CHANNELS x BIT RATE  
OCCUPIED BANDWIDTH  

Greater efficiency means that more voice and data traffic can be supported within a limited frequency range.  

 

 

Product

Channels

Average Data Rate

Channel Spacing

Frequency Reuse Factor

Spectral Efficiency (bits/sec/Hz)

PrimeWave 2000 (S-CDMA) with overhead

PrimeWave 2000 (S-CDMA) useable data

127

119

34Kbps

32Kbps

 3.5 MHz

3.5 MHz

1

1

1.234

1.088

IS-95 (CDMA) with overhead

IS-95 (CDMA) useable data

45

42*

9.6Kbps

9.6Kbps

1.25 MHz

1.25 MHz

1

1

0.346

0.323

Lucent Airloop (CDMA)

128

16Kbps

5 MHz

1

0.410

Interdigital Truelink/Samsung (B-CDMA)

89

32Kbps

15 MHz

1

0.190

Tadiran MGW (FH-CDMA – TDMA)

8

32Kbps

1 MHz

1

0.256

Hughes GMH2000R (TDMA)

3

8Kbps

30 KHz

3

0.266

Alcatel A9800 (DECT)

30

32Kbps

2 MHz

3

0.480

* Available channels depend on soft-handoff percentage (typically much less than 42)    

Synchronous CDMA – Perfect for Fixed Wireless Loop Applications  

The basic idea in reverse channel synchronous CDMA (S-CDMA) is that timing offset information is fed back from the base station to the subscriber units so that they may adjust their transmitter’s timing to all arrive at the base station within a small fraction of a chip of each other.  

This approach permits the use of truly orthogonal signature sequences for all of the users, assuming that the number of users in the system is no greater than the chip rate to channel symbol rate ratio. Due to the use of orthogonal signature sequences, many more users may be supported in a given cell or sector than in an asynchronous CDMA system. The capacity of such an asynchronous system is limited to the number of somewhat correlated/interfering users that can be supported without raising the interference noise floor to an unacceptable level. The number of users is typically about 1/3rd that of a comparable synchronous system.  

S-CDMA capacity is also higher than that achievable by TDMA or FDMA systems due to the lack of guard-bands and guard-times in isolated cell deployments. When multi-cell deployments are considered, the capacity of S-CDMA vastly exceeds that of a TDMA or FDMA system, due to the fact that every cell/sector can operate on the identical frequency band (referred to as, a frequency re-use of one). In contrast, TDMA and FDMA systems require that adjacent cells and sectors use different frequency bands to keep interference levels sufficiently low.  

In a wireless local loop telephone system where it is necessary to achieve very high availability’s (say 99.5% or higher) large margins are required in the link budget to combat fading. A common misconception is that there will be no fading in the fixed wireless local loop application, because subscriber units are not mobile. This simply is not true. Point to point microwave links, which are completely stationary and even have very high gain antennas, often experience fades of 40dB or higher. To combat this problem, a fixed wireless local loop system will need to have an effective fade margin in the order of 10dB to achieve link availability in the order of 99.5%.  

With S-CDMA, this kind of fade margin is achievable because the signal to interference ratio is so large due to the orthogonal signature sequence. In contrast, large fade margins are simply not achievable with an asynchronous CDMA system because in such a system the number of active users is increased until the signal to noise and interference ratio reaches a threshold which corresponds to a desired bit error. It is not possible to add additional margin to the asynchronous CDMA system without diminishing its capacity.  

Thus, S-CDMA provides the ability to achieve the high link availability necessary or the fixed wireless loop application. In addition, S-CDMA benefits from the advantages of traditional CDMA including a frequency reuse of one (1) in multi-cell deployments, a robustness to narrow band interference and an inherent resistance to eavesdropping due to the use of pseudo-noise spreading codes.

 

So if S-CDMA is such a good idea, Why isn’t every company doing it?  

L3 Communications is not starting the fixed wireless local loop product development from scratch. Instead we are simply building upon a foundation of spread spectrum and CDMA experience and products gained from many years of developing robust, covert military data links. Unlike most companies, L3 Communications has been producing spread spectrum and CDMA products for many years and so making the technological step to S-CDMA from traditional CDMA was not difficult.  

We have an innovative engineering staff that was able to solve the fundamental problems of synchronizing the system quickly, even when heavily loaded, and maintaining synchronization even on a multi-path channel, with an efficient timing control loop.  Prior to this development effort, these fundamental problems scared away other potential developers of S-CDMA technology. L3 Communications has either been granted, or has applied for over 12 international and US patents on these inventions that make S-CDMA possible.  

Finally, L3 Communications is not attempting to simply apply a mobile system solution to the fixed wireless local loop application. Instead, we started with a clean sheet of paper to create the system design. PrimeWave 2000 was designed from the ground up as a fixed wireless local loop system, so that we could optimize the system design to the application and apply fresh new ideas and the latest technology, including S-CDMA. This approach has produced the highest capacity and highest performance, wireless local loop product available today.  


- Profile - Contact - News - Hungary - Romania - Auction - Products - Services -
-En Espanol - En Francais - Magyar - Russian