Experiments were conducted to evaluate the viability of commercial-off-the-shelf (COTS) technology in the design of high-performance optical intersatellite communications links. The optical links were operated at 155, 622 and 2488 Megabits per second (Mbps) and at 1550 nm wavelength. Communications components were evaluated against performance parameters for on-off keyed (OOK) systems. Transmitters, receivers, optical amplifiers, and filters, used to minimize the impact of amplified spontaneous emission (ASE), were characterized individually and within system configurations. Bit error rate (BER) as a function of photons per bit was characterized for several system configurations. Extinction ratio analysis experiments were conducted to determine the limiting factors on the systems performance. Widely varying optical powers in space (for low earth orbit) imply a robust receiver dynamic range requirement. Dynamic range of COTS receivers was examined and resulted in sufficient performance. In addition, gamma radiation tests on fiber amplifiers were also evaluated in a system context.
Commercial high speed fiber optic transmitters and receivers were tested in a high energy proton environment at the Crocker Nuclear Laboratory to determine the transient impact of the space proton environment on a simulated communications link. The link was designed to simulate free-space communication between satellites. The transmit/receive bit error ratio was used as the evaluation metric. Individual electronic components on each transmitter and receiver module were tested using a variety of proton energies, angles of incidence, and optical link configurations. No change was found in the bit error ratio for any of the transmitters tested. Significant increases in bit error ratio were found on two of the receivers when several individual receiver components were irradiated. Small increases in bit error ratio were found on several receivers when exposed to 63 MeV proton fluxes greater than 1 X 107 p/cm2-s. The remaining receivers were found to be immune to the influence of the protons. This testing demonstrates the feasibility of operating commercial transmitters and receivers in a free-space optical link when exposed to the space proton environment.
Four Erbium doped fiber optic amplifiers (EDFAs) were irradiated by gamma-rays to dose levels of 40 Krad(Si) and 100 Krad(Si) at dose rates of 0.25 rad(Si) sec-1 and 1.0 rad(Si) sec-1, respectively. All EDFAs were observed to incur radiation induced permanent decreases to their pre-irradiated signal gains. The paper will discuss the influence of gamma-ray irradiations on EDFA parameters such as gain, noise figure, and integrated amplified spontaneous emission. A brief discussion of how changes to these parameters evolve is presented.
Access to the requested content is limited to institutions that have purchased or subscribe to SPIE eBooks.
You are receiving this notice because your organization may not have SPIE eBooks access.*
*Shibboleth/Open Athens users─please
sign in
to access your institution's subscriptions.
To obtain this item, you may purchase the complete book in print or electronic format on
SPIE.org.
INSTITUTIONAL Select your institution to access the SPIE Digital Library.
PERSONAL Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.