| Question | Answer |
| What are the main benefits of Microwave transmission? | -Quick Deployment of Links
-Flexibility & Scalability |
| Define frequency | Number of oscillations per second -- Measured in Hertz (Hz) |
| Impact of wavelength on MW range and deployment | Low Frequency = Long Distances
--Rural Areas
High frequencies = shorter distances
-Urban Areas |
| Distance range of MW Hop Length | Up to 150KM |
| Typical MW Frequency Range | 4-80GHz |
| Define Duplex Frequency | Distance between Tx & Rx frequency |
| Frequency band is divided into... | ...lower band and upper band. |
| What is Channel Width? Typical range? | Frequency bandwidth of a channel. Typical range is from 3.5MHz to 1000MHz. |
| What are the four traffic interfaces? Which are circuit switched networks and which are packet switched networks? | PDH (Circuit)
SDH/SONET (Circuit)
Ethernet (Packet)
ATM (Packet) |
| Define PDH. What is its ANSI & ETSI data standards? Deployment application? | PDH = Plesiochronous Digital Hierarchy (1960s)
-ETSI (E1) = 2Mbit/s
-ANSI (DS1) = 1.5Mbit/s
Deployed in lower capacity, short range capacities. |
| Define SONET and SDH. What is data stream rate and standard of each? Deployment application? | SONET = Synchronous Optical NETworking
-ANSI Standard 155Mbit/s (OC-3)
SDH = Synchronous Digital Hierarchy
-ETSI standard 155Mbit/s (STM-1) |
| Can a single E1 in SDH signal hundreds of E1's? Can a single STM-1 signal multiple STM-1's? | Yes and yes! |
| What is a Hybrid Radio Link? | Hybrid Radio Link can carry all traffic as TDM or Ethernet or a mix of the two. |
| Advantages of MW Deployment | -Short time to Market
-Quick Roll-Out
-Easy to Expand, Modular
-Low Investment (invest as you grow)
-Low Operational Costs (install and forget)
-Application Independent
-Software Controlled Functionality |
| Timeline for MW Technology | 1930's - Start of use for MW as a transmission resource (analog signals)
1970 - MW Links produced at Ericsson. In mid 70's, first digital link
Mid 1980's - MW Links premiere in cellular networks
1990's - Digital Mobile Networks & TDM's |
| What percentage of radio base stations worldwide are connected via microwave? | 60% |
| Microwave Mobile Backhaul Applications | -Supporting 2G,3G,4G/LTE
-High capacity Fiber ring closure
-TDM only transport
-Hybrid Transport
-All Packet Transport |
| What is MIMO? | MIMO - Multiple Input & Multiple Output
--Increases MW capacity using multiple transmitters and multiple receivers. |
| What are the 3 ways to build a microwave system? | 1) All Outdoor
2) All Indoor
3) Split Mounting |
| Unprotected vs Protected Mode | Unprotected Mode = Single point of failure can lead to a complete loss of the connection.
Protected Mode = System is redundant. |
| Name the 4 different subnetworks of a MW Transmission Network | 1) Radio Network - MW radio communication to carry traffic, synchronization, and management.
2) Traffic Network - Distribution of traffic from "switching site" to "the last site."
3) Management Network - Supe0
4) Synchronization Network |
| Define the Radio Network MW subnetwork. | |
| Define the Traffic Network MW subnetwork. | |
| Define the Management Network MW subnetwork. | |
| Define the Synchronization Network MW subnetwork. | Transport of synchronization signal from the "Switching site" to transmission equipment and radio base stations. |
