Concept of All-Optical Ultra-Wideband Electronic Warfare Receiver André Paim Gonçalves Departamento de Eletrônica, Instituto Tecnológico de Aeronáutica, ITA São José dos Campos/SP – Brasil Robson Ribeiro Carreira Departamento de Eletrônica, Instituto Tecnológico de Aeronáutica, ITA São José dos Campos/SP – Brasil Joaquim José Barroso de Castro Departamento de Eletrônica, Instituto Tecnológico de Aeronáutica, ITA São José dos Campos/SP – Brasil Abstract: This paper presents the theoretical and experimental concept of an all-optical ultra-wideband Electronic Warfare receiver based on an envelope detector with a 100% probability of intercepting broadband signals and can be miniaturized and integrated. Its operating range in RF can reach over 100 GHz depending on the phase modulator and the stopband of the fiber Bragg grating used. Its instantaneous bandwidth can reach over tens of GHz depending on the photodetector. The proposed architecture does not need an optical or video signal amplifier. The implementation of this conceptual receiver is simple, employs few components and uses inexpensive components found in the shelf. Its miniaturized version can be used in remotely piloted aerial vehicles and satellites due to its low power consumption, small weight, and volume. Index Terms—Envelope detection, ultra-wideband, microwave photonics. I. INTRODUCTION With the advent of the use of satellites and remotely piloted aircrafts in electronic warfare, we can see the growing need for reduction of energy consumption, low volume and weight, as well as large radio frequency bandwidth [1]. The microwave photonics emerged to overcome the electronics in the fulfillment of such a difficult requirement. Faced with this challenge, the potentialities of using microwave photonics to reduce weight, volume, consumption and increase the bandwidth were studied [2]. Some architectures emerged proposing the detection of signals with these characteristics [3], [4], and [5]. However, both architectures employ intensity modulators that demand for a rigorous bias voltage Olympio Lucchini Coutinho Departamento de Eletrônica, Instituto Tecnológico de Aeronáutica, ITA São José dos Campos/SP – Brasil José Edimar Barbosa Oliveira Departamento de Eletrônica, Instituto Tecnológico de Aeronáutica, ITA São José dos Campos/SP – Brasil Felipe Streitenberger Ivo Departamento de Eletrônica, Instituto Tecnológico de Aeronáutica, ITA São José dos Campos/SP – Brasil control systems to avoid drift on the quadrature operating point [6]. It is noteworthy that these devices employ several photonic and electronic components, which make difficult their miniaturization by silicon photonics. The proposal of this work is an architecture that employs a laser, an optical phase modulator, an optical filter, and a low speed photodetector. The proposed architecture uses photonic self-homodyne detection, bringing the additional advantage to reduce the optical carrier power at the photodetector, and thus drastically reduce the shot noise [6]. The RF-to-optical conversion enables photonic signal processing that can reduce the complexity of the RF hardware front-end [6]. This receiver does not claim for optical or electronic amplification and it has few components, which allows a future miniaturization. Because it employs a phase modulator, it does not depend on a modulator bias control circuit. Since the receiver output signal is at the base band, the photodetector used in this approach can be low speed, reducing the cost and complexity of implementation. For the case of pulses with an instantaneous bandwidth below 1.5 GHz, it is still possible to employ such a photodetector. The receiver consumes little energy because its few components are mostly passive and have low energy loss through coupling and absorption. This receiver has a 100% interception probability because it does not have to beat frequencies from local oscillators. This characteristic is observed in Radar Warning Receiver (RWR) [7]. Its RF operating range may exceed 100 GHz considering the use of phase modulators based on plasmonic technology [8].