ETCP Ericsson Microwave and Transmission Solutions 1 — Questions and Answers
Question 1: What does XPIC stand for in Ericsson MINI-LINK microwave systems?
- Cross-Polarization Interference Cancellation (Correct answer)
- Cross-Path Interference Control
- Cross-Polarization Interference Correction
- Cross-Path Isolation Circuit
Correct answer: Cross-Polarization Interference Cancellation
XPIC stands for Cross-Polarization Interference Cancellation, enabling both polarizations on the same frequency to double spectral efficiency.
Question 2: Which Ericsson product family is the primary platform for microwave backhaul?
- Ericsson RBS 6000
- MINI-LINK (Correct answer)
- Ericsson MSC-S
- Ericsson SGSN-MME
Correct answer: MINI-LINK
Ericsson's MINI-LINK product family is specifically designed and marketed for microwave backhaul applications.
Question 3: What is the primary purpose of Adaptive Coding and Modulation (ACM) in a microwave link?
- To increase physical antenna aperture
- To adjust modulation order and coding rate based on current link conditions (Correct answer)
- To replace frequency planning entirely
- To manage IP routing table updates
Correct answer: To adjust modulation order and coding rate based on current link conditions
ACM dynamically lowers the modulation order during signal degradation (e.g., rain fade) to maintain link availability at the cost of reduced throughput.
Question 4: Which synchronization standard provides phase and time synchronization required by LTE and 5G in Ericsson microwave backhaul?
- SONET OC-3
- SDH STM-1
- IEEE 1588v2 (PTP) (Correct answer)
- NTP v4
Correct answer: IEEE 1588v2 (PTP)
IEEE 1588v2 (Precision Time Protocol) delivers sub-microsecond phase/time accuracy needed for LTE TDD and 5G NR synchronization.
Question 5: What frequency range defines the E-band used in high-capacity Ericsson MINI-LINK deployments?
- 6–11 GHz
- 18–23 GHz
- 38–42 GHz
- 71–86 GHz (Correct answer)
Correct answer: 71–86 GHz
E-band occupies 71–86 GHz, offering large channel bandwidths (up to 2 GHz) that enable multi-gigabit backhaul over short distances.
Question 6: What does ATPC stand for in Ericsson microwave transmission systems?
- Automatic Transmit Power Control (Correct answer)
- Adaptive Transmission Protocol Configuration
- Automatic Traffic Priority Control
- Advanced Topology Path Control
Correct answer: Automatic Transmit Power Control
ATPC (Automatic Transmit Power Control) reduces transmit power during clear conditions to minimize interference and save energy, increasing power only when the link fades.
Question 7: What is the primary advantage of a hybrid microwave solution that combines fiber and wireless links?
- Eliminates all fiber infrastructure costs
- Provides path diversity for increased resilience and aggregate capacity (Correct answer)
- Simplifies frequency coordination requirements
- Reduces end-to-end latency below that of pure fiber
Correct answer: Provides path diversity for increased resilience and aggregate capacity
Hybrid microwave bonds a fiber path and a wireless path, so if one path degrades the other compensates, improving both availability and total capacity.
ETCP Ericsson Microwave and Transmission Solutions 1
What does XPIC stand for in Ericsson MINI-LINK microwave systems?