For system engineers working on radar, electronic countermeasures, or broadband wireless infrastructure, selecting the right optical component is a mission-critical decision. The choice often comes down to two leading candidates from NEON(https://www.neoncq.com): the NY13T and NY15T series UWB directly modulated transmitter. While both modules share a common design philosophy—integrating a high-speed DFB laser with automatic power and temperature control circuits—they are optimized for different wavelength windows, each with unique advantages in fiber-optic transmission. Understanding the subtle but important differences between these two UWB directly modulated transmitter families is essential for maximizing link budget, minimizing dispersion, and ensuring long-term reliability in the field.
The NY13T series UWB directly modulated transmitter (https://www.neoncq.com/ny13t-series-uwb-directly-modulated-transmitter) operates at a nominal wavelength of 1310nm. This wavelength is significant because standard single-mode optical fiber exhibits zero dispersion at 1310nm. Dispersion is the phenomenon where different spectral components of a light pulse travel at slightly different speeds, causing the pulse to spread out. In a UWB directly modulated transmitter, some degree of frequency chirp is inevitable. By operating at 1310nm, the NY13T minimizes the impact of this chirp, allowing the optical signal to travel several kilometers without significant pulse broadening. This makes the NY13T ideal for medium-distance links, such as distributing RF signals within a large campus, a ship, or an aircraft. With a modulation bandwidth better than 18GHz and output power up to 10mW, the NY13T UWB directly modulated transmitter provides ample performance for X-band (8-12 GHz) and Ku-band (12-18 GHz) radar and communication systems.
In contrast, the NY15T series UWB directly modulated transmitter (https://www.neoncq.com/ny15t-series-uwb-directly-modulated-transmitter) operates at 1550nm. While 1550nm fiber has higher dispersion than 1310nm, it has significantly lower attenuation (approximately 0.2 dB/km vs. 0.35 dB/km at 1310nm). For long-distance links exceeding 10 kilometers, the lower loss of the 1550nm window becomes the dominant advantage. The NY15T UWB directly modulated transmitter is therefore the preferred choice for terrestrial long-haul links, such as connecting remote radar sites to a central processing center, or for distributing cable TV (CATV) signals over many kilometers. To combat the dispersion issue at 1550nm, the NY15T employs a DFB laser with a very narrow linewidth and optimized chirp characteristics. Additionally, the NY15T features excellent side mode suppression ratio (SMSR), ensuring that nearly all the optical power is concentrated at the desired 1550nm wavelength, minimizing interference and power loss.
Both the NY13T and NY15T UWB directly modulated transmitter modules are designed for harsh environments. They feature a wide operating case temperature range of -40℃ to +70℃, making them suitable for outdoor tower installations or unheated shelters. The robust packaging includes an SMA RF connector for signal input and a military-grade J30J-9-ZKP power connector for reliable DC power delivery (accepting +7V to +36V). Internally, the automatic power control (APC) circuit compensates for laser aging and temperature changes, maintaining a constant average optical power. The automatic temperature control (ATC) circuit uses a thermoelectric cooler (TEC) to keep the DFB laser chip at a precise setpoint. These features ensure that the UWB directly modulated transmitter delivers consistent performance over years of service. For engineers designing next-generation wireless systems, the choice between the 1310nm NY13T and the 1550nm NY15T UWB directly modulated transmitter allows for optimization based on link distance, dispersion tolerance, and existing fiber plant infrastructure.
