Dual Band Microstrip Patch Antenna Design

I'm seeking a skilled RF engineer to design a dual-band single-feed microstrip patch antenna for L1 and L2 bands, using RT5880 substrate. The entire antenna must fit within a 13cm x 13cm footprint and be modeled in CST.

Key Requirements:
- Frequency Range: L2 (1164 - 1255 MHz), L1 (1559 - 1610 MHz)
- VSWR: < 1.3:1 (L2), < 1.4:1 (L1)
- System Gain at Zenith (@5V): L2 (22.4 ~ 31.3 dBic), L1 (25.8 ~ 26.7 dBic)
- Axial Ratio at Zenith: L2 (Typ. 1.7 dB), L1 (Typ. 1.0 dB)
- Average Gain (Cable loss included): L2 (18.9 dBic), L1 (19.6 dB)
- Noise Figure (@5V): L2 (Typ. 1.9 dB), L1 (Typ. 1.6 dB)
- Group Delay @ Zenith: L2 (13.9 ns), L1 (23.2 ns)
- Phase Center Variation (PCV): Max ±2.0 mm
- LNA Supply: DC Voltage Range (3.0 ~ 5.0V), Current (15.0 mA @ 5.0V)
- Feed Point Impedance: 50 Ohms
- Polarization: RHCP (Right-Hand Circular Polarized)

Ideal skills and experience:
- Expertise in microstrip patch antenna design
- Proficiency in CST modeling and simulation
- Strong understanding of RF specifications and requirements
- Experience with RT5880 substrate and low-loss materials

Please provide a portfolio showcasing relevant experience and similar projects.