## 1 Introduction  
Radio-over-fiber (RoF) links assisted by integrated microwave photonics (MWP) are expected to play an important role in the fifth generation (5G) and beyond [1]. With the ever-increasing demand for higher bandwidths, technologies have moved toward higher-frequency bands, such as the millimeter-wave (mmW) bands [2]. Unfortunately, wireless transmission in the mmW range is limited by the attenuation caused by the non-transparent obstacles and absorption in the atmosphere [3]. Therefore, among other reasons, fiber-based communication is envisioned in certain parts of the future-generation radio access network (RAN) [4, 5]. Nevertheless, the well-known advantages of fiber optics, such as low attenuation, extensive bandwidth, immunity to electromagnetic interference, and compatibility with microwave photonic systems, come at a price. When signals in the mmW frequency range are transmitted over standard, single-mode fiber (SMF) in analog RoF (A-RoF) format, such as Intermediate Frequency over Fiber (IFoF) or Radio-Frequency over Fiber (RFoF), the non-zero chromatic dispersion at telecom wavelengthscauses group velocity dispersion (GVD). In an intensity-modulated A-RoF link, given its typical double-sideband spectral profile, this causes a relative phase shift between both sidebands and effectively presents us with an unfavorable frequency- and length-dependent power fading [6]. While there are several ways [6; 7; 8] to mitigate this issue, introducing a two-color signal, such as an optical single-sideband (OSSB) signal [9; 10] or an optical double-sideband (ODSB) signal with a suppressed carrier (SC) [11; 12; 13; 14; 15], is a robust and universal solution that does not depend on the fiber's length and can therefore be applied to various optical network topologies, e.g., point-to-multipoint. A wide variety of techniques for establishing a two-color spectral profile has been proposed and demonstrated. However, with advances in photonic-integrated-circuit (PIC) manufacturability, photonic solutions are becoming increasingly attractive. One such example is a simple add/drop micro-ring resonator (MRR) [16], exhibiting a multi-stopband filter response in the input-through direction, which can be used to suppress one of the sidebands in an ODSB modulation scheme, as demonstrated in our previous publication [17]. Several other research papers also report on similar approaches, while using the somewhat more complex MRR-based photonic structures [18; 19; 20]. This paper further investigates a solution employing an MRR to suppress one of the sidebands and addresses the inherent, yet undesirable, temperature instability of the MRR and its optical transfer function (OTF). MRRs are highly susceptible to temperature fluctuations, with a typical temperature dependence in the range of tens of pm/K for silicon-on-insulator technology [21]. This causes the resonant wavelength(s) to shift over time, worsening the sideband-suppression ratio (SBSR), which reintroduces the power fading. Researchers have investigated different approaches to overcome the challenges of MRR temperature dependence [22]. Existing approaches mostly fall into two categories: (1) approaches that permanently reduce the temperature dependence of MRRs to very low or near-zero values by altering their structural and/or material properties, so-called athermal solutions, and (2) the ones that actively control their instantaneous material and/or geometric properties by means of thermo-optic- (TO) [23; 24] or electro-optic- (EO) effect-enabling elements. While athermal solutions might effectively eliminate the temperature dependence of the MRR, it might not guarantee its relative wavelength alignment with the laser of an RoF transmitter. Solutions from the second category rely on some kind of feedback information, reflecting the state of the MRR's OTF, which is then processed by the control system, acting on the tuning mechanism, e.g., the integrated heaters.