###### Abstract  
One of the most efficient methods to observe the impact of geographical, environmental, and geological changes is remote sensing. Nowadays, nanosatellites are being used to observe climate change using remote sensing technology. Communication between a remote sensing nanosatellite and Earth significantly depends upon antenna systems. Body-mounted solar panels are the main source of satellite operating power unless deployable solar panels are used. Lower ultra-high frequency (UHF) nanosatellite antenna design is a crucial challenge due to the physical size constraint and the need for solar panel integration. Moreover, nanosatellite space missions are vulnerable because of antenna and solar panel deployment complexity. This paper proposes a solar panel-integrated modified planner inverted F antenna (PIFA) to mitigate these crucial limitations. The antenna consists of a slotted rectangular radiating patch with coaxial probe feeding and a rectangular ground plane. The proposed antenna has achieved a \(-10\) dB impedance bandwidth of \(6.0\) MHz (\(447.5\) MHz\(-453.5\) MHz) with a small-sized (\(80\) mm\(\times\)\(90\) mm\(\times\)\(0.5\) mm) radiating element. In addition, the antenna achieved a maximum realized gain of \(0.6\) dB and a total efficiency of \(67.45\%\) with the nanosatellite structure and a solar panel. The challenges addressed by the proposed antenna are to ensure solar panel placement between the radiating element and the ground plane, and provide approximately \(55\%\) open space to allow solar irradiance into the solar panel. remote sensing CubeSat; deployment free; nanosatellite; modified PIFA; UHF antenna; UHF communication [1][]and uplink-downlink communications. Solar panels are used to manage the required power, and antennas are used to establish uplink-downlink communications. The ultra-high frequency (UHF)-band, especially the frequency range 420-450 MHz, is highly desirable for nanosatellite researchers, because the International Telecommunication Union has allocated this band as the International amateur satellite frequency band [6]. Antenna design for nanosatellites especially for lower frequencies presents its own challenge and has been a critical matter for CubeSat researchers [7]. In addition, solar panel integration presents another major problem because of the limited surface of the nanosatellite body [8]. These limitations were overcome by using deployable solar panels and antennas in recent nanosatellite missions [9]. However, mechanical deployment is quite sophisticated and this might increase the chance of mission failure [10]. Several small satellite missions have failed as a result of antenna deployment complexity [11; 12] and solar panel deployment complexity [13]. In contrast to the deployable antenna, the patch antenna is an effective replacement to improve mission reliability. However, a UHF patch antenna occupies a large area of the nanosatellite body surface and introduces complexity in terms of integrating sufficient solar cells. Various approaches have been reported to address the problem of integrating a solar panel with the antenna [14; 15]. For instance, transparent antennas were placed above the solar panels on the CubeSat. Even though transparent antennas provide up to 90% of transparency for solar penetration, these types of antennas require expensive transparent substrates such as quartz or Lexan. In addition, their fabrication process is complex and expensive. Nontransparent subsolar antennas are placed beneath the solar panels with the constraint that the patch must not be covered by the solar panel, and this enlarges the antenna size for lower UHF applications [14; 16]. Thus, designing an UHF antenna that is strategically integrated with the solar panel and that does not require mechanical deployment has become a major challenge for nanosatellite and antenna researchers. This paper proposes a nanosatellite body-mounted slotted planner inverted F antenna (PIFA) antenna for a remote sensing UHF communication system.