PMRTS(Public Mobile Radio Trunking Services) INTRODUCTION VHF wireless system – Is a radio to radio communication, where repeaters were used to increase the coverage area. PMRTS – Public Mobile Radio Trunking System – In this a pool of frequencies are dynamically reused by many customers. It is similar to a wireless EPBX. Analog PMRTS Analog PMRTS Vs. VHF system •In VHF five frequencies are used by five customers, whereas in Analog PMRTS five frequencies can be used y more than 40 customers at a time. •In VHF the distance covered is limited, whereas in Analog PMRTS one full city can be covered (Power radiated is 100W). In VHF individual customers have to pay for the use of frequencies, whereas in PMRTS the Service Provider pays and collects revenue from the individual customers. it means that your radios automatically get a free 'path'.What is PMRTS ? Public Mobile Radio Trunking Service (PMRTS) is an instant. at the press of a button. When radio channels are trunked. even if some or all of them are on the move. (i. to communicate with each other. PTT) . two-way mobile (radio) communication service that allows a group of people to communicate with each other.e. The Trunking system was then developed to more efficiently meet the communication needs of a large amount of users by sharing a small number of frequencies. frequency congestion occurs since there are only a finite number of frequencies. As the numbers of users grow. . PMRTS is basically sharing of radio channels amongst a number of different user groups on the same system without interfering with each other's conversations.Need for PMRTS Conventional system is the foundation of two way radios. • Analog Trunking services were started in India in 1996. the guidelines for Digital PMRTS got released. BPOs.. In 2001. cost of hand sets and technology constraints contributed to slow growth rate of this industry. • Several traditional users of Trunking services migrated to other wireless technologies due to above limitations. Call centers. • Over a period of time analog PMRTS got consolidated and two serious players left out. • Despite several constraints. . realized importance of Trunking concept and subscribed to this service. regulatory roadblocks. Taxi fleets etc.History of PMRTS ( Analog and Digital Trunking Services) • Citywide Analog Trunking licenses were issued in 1995. segments including IT. Serious players remained. • Poor hand set design. • Several Trunking operators disappeared. • Consolidation of Trunking industry completed by 2000 with two major players remaining in the market. iDEN. ZTE • Three different technologies namely. • iDEN and TETRA are based on TDMA and Gota is based on CDMA. Gota – ZTE. TETRA & Gota. • iDEN – Motorola.Technology & Worldwide Vendors Analog • Vendors: Motorola & Kenwood • Smartnet (Motorola Proprietary). LTR (Open standard) Digital • Vendors: Motorola. . Tetra – Motorola. 800MHz and 900 MHz bands. handset locking / vendor specific handsets are vendor specific. there is no Since it is proprietary standard. handset. Since it is open standard. Evolution of new generations & handshaking with new technologies are highly possible. 8 2 3 4 . Not Proprietary. No 1 Cellular (GSM) Digital PMRTS Technology is open standard. Completely the vendor specific. Easily adoptable depends on the vendor. Can work in 900MHz & 1800MHz bands New generations & handshaking with multiple technologies depends on vendor interest. Can work in 400Mhz.Comparison of GSM and PMRTS Sl. Roaming not allowed.Comparison of GSM and PMRTS 5 6 7 Prepaid & other IN services Prepaid & other IN services are possible are not possible National & International roaming allowed. Can have own numbering scheme Can have PoI with all operators. Don’t have own numbering scheme. Inter-circle connectivity is allowed. 8 9 9 . No inter operator POI Connectivity limited to the same circle. Depends on PSTN. Can have PoI through PRI from one of the PSTN. 470 MHz and 336-360 MHz in 400 MHz band Band Width required for (Analog and Digital PMRTS).935-941(Down-link) 300/400 MHz & 800 MHz band: 405.Frequency Bands for PMRTS Frequency Band of PMRTS In India: Analog: 814-819(up-link). 859-864(Down-link) Digital: 811-814 (Up-link). Channel Separation .25 KHz in 800 MHz Band and 12.851-870(Down-link) Digital: 806-825 (Up-link).851-870(Down-link) 896-902 (Up link).5 KHz in 300/400 MHz Band .856-859(Down-link) Frequency Band for PMRTS Worldwide: Analog: 806-825(Up-link). Spectral efficiency of PMRTS. 11 . Equipment Diagram of a Digital PMRTS RF link Fiber Optic Mobile Handheld Controller Base Unit Repeater Base unit EBTS Cell site (Enhanced Base Site) 12 . g. GPS . (HH) BTS 1 BILLING SYSTEM Ethernet cable BTS 2 Optic Fiber Link BACKHAUL Connectivity Ethernet cable D A C S MSO Ethernet cable BTS 3 Digital access cross connect switch. for multiplexing BTS 48 Other Servers.NETWORK LAYOUT DIAGRAM Hand held. AAA. . required to run the system e. Overall Infrastructure • EBTS RF Distribution Base Radio Integrated Site Controller Airtel Frame Relay Over E1 Controller Dispatch Application Processor Other MSO Elements Ethernet MSO Power Supply E1 PSTN / PBX Required DID 14 . on-line Games. MSO (Controller. DAP – Dispatch Application Processor. Controller Rack (used to control the signals. Major Components : 1. MDG etc) (MSO – Mobile Switching Office.Description of Network Elements MSO : EBTS Connectivity through DACS. 3. Navigation etc). used for fault monitoring in the BTS sites) Base Radio (used for increasing the RF power received and increasing the output ) MIBAS (Billing Server) Provisioning & Billing related activities is done by MIBAS (Motorola Integrated Billing Access System) VAS (Value Added Service) All data related applications (e-mail. Call routing . 2.Home Location Register. HLR. Registration and Authentication etc Major Components: 1.Call delivery. coverage & an RF Interface to the Handheld. DAP. Announcements. 15 . used to multiplex the time slots from the BTS) ransmission Rack (Used to connect the remote BTS / Cell Sites to the MSO via DACS) EBTS : (Enhanced Base Station/Cell Site ) Responsible for call maturity. RF Rack (Used for transmission and reception of RF signals) 3. 4. HLR . signals handhelds) 2. MDG – Mobile Data Gateway) DACS (DACS – Digital Access Cross Connect Switch. ISC 3 (Integrated Site Controller. Limitations of Analog PMRTS Large size of handsets Limited choice of models that too bulky Minimum Loading/Channel is 90 Mobiles. High cost of handsets Inability to address vast potential – Capacity constraints Heavy Weight in comparison with GSM Handsets . Increase in the coverage area. Analog PMRTS Slim and low cost handsets.Digital vs. High quality of voice and complete privacy of voice digital technology. Minimum Loading/Channel is much higher than Analog. Support GPS Secrecy maintained Better spectral efficiency with . 18 . • Separate licenses shall be granted on a non-exclusive basis for each service area of operation. • PMRTS providers shall be eligible to obtain licenses for any number of service areas.• PMRTS providers shall provide mobile radio trunking services within their service area of operation. • Licenses would be awarded for an initial period of 20 years and will be extended by additional periods of 10 years thereafter. 3. Handsets/ Base Stations/MSO and other switching units are pertaining to the Internationally approved Manufacturers and standards. Adjacent Channel Spacing as per the norms (Should not be more than 25 KHz) 8. Power Output limits of Base Station/Handheld/Vehicle Mobile sets. 4. The Number of Channels / Frequencies required are justified or not. Number of Fixed Stations should not be more than 10% of the Total Subscribers 19 . The Technology offered is of an OPEN Standard ie in accordance with ITU/ TEC/ ETSI/ International Standard. 7.Technical Advice by TEC Technical documents submitted by Vendor / Applicant are examined by TEC and thereafter Technical Comments are sent to DoT (CS Cell) before issue of License. Frequency band as per latest NFAP ( 300/400/800 MHz) 6. 2. TEC Examines basically the following Parameters: 1. Coverage of Base Station ( Range should not be more than 30 Kms) 5. Frequency Reuse 20 . Phillippines. • India has launched its 1st Commercial Digital PMRT services in Bangalore ( Karnataka State ) in the year 2007. Coal Mining Industries BSF ( Border Security Forces ) etc. but most of these Networks are individual Captive Networks being used by all most all the Airports. Indonesia and India have Analog or Digital PMRTS Network.Korea. day to day secure working of the Private Telecom Network providing prompt actions / Services and maintaining Law & Order with full Security.Argentina. CMRTS ( Captive Mobile Radio Trunking Service ) Captive PMRTS are used for efficient. Railways. Many countries like USA. Oil Refinaries. Coal Mining Agencies. Police Head Quarters or Other Police Branch Offices.Israel.Mexico. iDEN and MPT 1327 etc. Smart Trunk Ii. 21 . Private and Public Sectors Enetrprises for their own Secure • • • • Telecommunication Networks.Deployment of Analog and Digital PMRTS in India and World • • • • There are basically two types of Public Mobile Radio Trunking Services available in India and all over the World which are as follows :1. Such types of Services are used only for a particular Service Areas and not for commercial uses of all the public Departments like Airports. EDACS. Japan.Malaysia.Saudi Arabia. 2.Canada.iDEN and other technologies providing an unlimited number of users in the same Digital Network covering large cities service areas. PMRTS ( Public Mobile Radio Trunking Service ) These are the Services used by Public on Commercial Basis using either Analog or Digital technologies with latest features and facilities provided for the operators and users. Police Head Quarters .Brazil. Metros.But recently all most all the existing as well as New Applicants are entering this field with Digital Technologies and previous existing networks are migrating from Analog to Digital.China. APCO-25. These Digital Networks are based on TETRA.Singapore.Peru.Jorden. Metros.Chile.Crude Oil Companies/ Refinaries. Earlier these networks are generally based on various Analog Technologies like LTR (Logic Trunked Radio).Cuba. 22 . Whether the company has an approved MOU with the foreign Collaborator who will be supplying the Equipment along with the proper training to the concerned staff. it is essential to considered the following points very carefully : Whether the applicant has the sufficient knowledge or know how of the proposed system / Technology. Providing full assistance and co-operation during installation/validation /trial of the system / equipments well before the targeted period. Gota. Standards viz. Whether the Proposed Technology / Equipment / System is going to be used by the DOT/ Police Network/Airport/Metro/ or any other Govt. iDEN. LTR etc . APCO-25 Whether the System proposed will have full Security System / Reliable in terms of Secracy / Guarantee of Maintenance / Availability of Spares Handsets/ Redundancy of the Equipment.Motorola. before issue of Licenses to the concerned Applicants.Present requirement of DOT ( Action Items by TEC ) To successfully implement this latest design Analog or Digital PMRTS Systems in various Technologies like Tetra. Whether any of his Engineers / Officials have been trained in the proposed System. Smartnet. ./Public Sector is based on Open Technology ie as per the World Telcom. ETSI. Examples 24 . And even in India tetra technologies are being used in almost all the networks of Airports. Tetra and Gota. First network had already been launched and commercialized at Bangalore for which the TSTP had also been prepared and approved by TEC. spectral efficient and has been in existence for over 15 years and Its handsets are less expensive than the Tetra handsets. predominantly used a Captive Network. mainly for Public safety applications and disaster management operations. 1. Tetra has several captive network installations all over the world. At present it is not used anywhere in India. Tetra is being used for Captive use. metros & Police head quarters . 25 . • 2. iDEN is robust.There is no successful commercial operation of Gota installation so far in India.iDEN: iDEN ( Integrated Digital Enhanced Network Technology) is Motorola’s • Propriety Technology and is presently working in 22 countries and is suitable for commercial applications .Different Digital PMRTS Technologies present • • Three popular Digital Trunking Technologies are iDEN. 3. TETRA: TETRA is an European Open Standard . GOTA: GOTA it is a Chinese Propriety Technology. • • • 26 . viz..Trends in PMRTS industry • Majority of countries are migrating to Digital PMRTS.Indonesia.Malaysia. • 5 countries in Asia.Vietnam and Bangladesh region are migrating to Digital PMRTS this year. Customers understand that their Push-to-talk Group call requirements are best met by iDEN / Tetra / GOTA technologies and not by GSM or CDMA which at best offer CUG feature. Thailand. More Group calls can be effectively established only with the help of additional spectrum. Push-to-talk (PTT)-Group Call market will continuously expand as business industry grows. Future Scope • Market for Digital PMRTS services will continue to grow. 27 . • Technology suppliers must also think of introducing latest multiplexing technologies to bring more efficiency. The call will not get through because of the following conditions: the Handheld is out of coverage area the Handheld is busy. The call will get through only if the following conditions are met: the handheld is in coverage area the handheld is not busy. • • • • • • • 28 .Digital PMRTS w/o DID • • In the case where the Digital Public Mobile Radio Trunking Service Provider does not have Direct inward Dialing (DID) then: The call made from a landline or Mobile Phone to the Digital PMRTS. gets matured. In all the above cases the calling party will be billed just after the call lands on the EPBX & giving voice prompt. and need to dial required internal number. and the and the calling party will be metered from the same instance and thereafter hears a voice prompt. It will first land on the EPBX of the Digital PMRTS. 000 per piece) The growth and demand is limited.Difference between ANALOG & DIGITAL Handset ANALOG HANDSET • Much more like a 2 Way Radio Output power is very high (up to 3 watts) Weight of the Handset is huge (>500 gms) Value added features not available The cost of handset is very high (approx Rs. Police etc. • • • • • 29 . 20. Hotels. being an old technology and is generally required for Captive Networks like Airports. Difference between ANALOG & DIGITAL Handset DIGITAL HANDSET : • Form Factor (size) is smaller Output power is very low (0. • • • • 30 . Tele-voting etc.6 watts) Weight of the Handset is light (100 gms) Dual Communication – PTT and ability to Interconnect (if DID is available) Supports Data applications like Email. to offer the City wide Trunking system. Different Analog PMRTS technologies presently available are : 1. Smartnet II from Motorola 2. MPT1327 from Marconi .Analog PMRTS Technologies present Analog PMRTS was rolled out in the year 1997.These analog systems are working successfully even today but with limited features & customers. LTR(Logic Trunk Radio) from Kenwood and EF Johnson 3. Initially five frequencies are issued for a smaller city like Jaipur and for large cities like Delhi ten frequencies are issued initially by WPC to rollout the network . The number of customers that can be accommodated in a digital system are much more than a analog system to the tune of 30.000. unlike Analog system. . Digital PMRTS offers the option of reuse of frequencies. the end customer will have better on-street coverage with less interference.Digital PMRTS Technology Digital PMRTS is being rolled out to offer several advantages over the existing Analog Systems It is an extension of the existing analog technology It is a multi – site system unlike a single site system in analog .(subject to the digital system getting minimum number of frequencies to rollout an interference free network) It is a frequency efficient system .as the number of frequencies are reused and the number of sites are more. (subject to sufficient frequencies available and system capacity). 5. Group Calls & Private Calls are available. 3. Data enabled applications are available .Advantages of digital System Following are some of the advantages of Digital PMRTS System : 1. 8.6 W (max) thereby reducing the uplink 7. 4. Different range of handsets are available. SMS Services available. . Handset operates at 0. Offers superior voice quality 2. Ability of providing a fully duplex communication when a call is made to or received from the PSTN network. There is no limit to the number of subscribers in a group. 6. 34 .