Voice Engineer Lisboa

Voice Engineer
Lisboa
Lisboa, Lisboa, Portugal

Voice Core Engineer – Lisbon (Hybrid)

Location: Lisbon, Portugal

Work Setup: Hybrid – 2 days per week onsite

Start Date: ASAP

Contract Duration: Until March 2026 (with strong renewal history)

Role Overview:

We are seeking an experienced Voice Core Engineer with a strong background in IMS and CS core networks. The ideal candidate will have
- on expertise in Vo
LTE architecture, signaling protocols, and core network nodes, and will play a key role in supporting and optimizing voice services.

Key Responsibilities:

• Operate and maintain IMS/CS Voice Core network components including SBC,
  - CSCF, TAS, BGCF, MGCF, MRF, MGW, MSC, IMMGW.
• Analyze and troubleshoot IMS voice flows and procedures (e. g. , Vo
  LTE-Vo
  LTE calls, TADS, Homing, Break-in/out calls).
• Understand and manage subscriber profiles in HSS/HLR and their impact on network behavior.
• Work with Vo
  LTE-related protocols: SIP, Diameter, DNS, H248, Camel, RTP/RTCP.
• Support Vo
  LTE/Vo
  Wi
  Fi architecture and concepts.
• Collaborate with
  - functional teams and contribute to
  - facing engagements.

Preferred Experience:

• Familiarity with HSS, HLR, Cu
  DB.
• Experience with signaling transfer elements (DRA, STP).
• Knowledge of DNS/ENUM and Number Portability (NP).
• Exposure to vendor technologies: Huawei, Oracle, Ericsson, Mavenir, Nokia.

Qualifications:

• BSc or MSc in Electronics, Telecommunications, or Computer Engineering.
• Certifications from Ericsson, Huawei, Nokia, or Cisco are advantageous.
• Strong communication skills in Portuguese and English.
• Proven ability to plan, prioritize, and work proactively in a team environment.
• Previous experience working with telecom operators in
  - facing roles.