Communication over multimode and single mode fiber

A communication module comprising:

• two or more lasers configured to produce light signals;
• a multiplexer (MUX) configured to receive the light signals and multiplex the light signals into a wavelength division multiplex (WDM) optical signal;
• and
• a transmitter optical sub assembly (TOSA) receptacle that launches at least a portion of the WDM optical signal to an optical fiber, wherein:
• the TOSA receptacle includes a receptacle length that is configured such that higher order modes of an optical signal received by the TOSA receptacle are not completely attenuated prior to being launched onto the optical fiber, and
• the higher order modes included in the optical signal are at least partially determined by the receptacle length of the TOSA receptacle and a core diameter of the TOSA receptacle.

A method of increasing modal bandwidth in a communications link, comprising:

• producing an optical signal;
• optically communicating the optical signal to a transmitter optical sub assembly (TOSA) receptacle;
• launching a quasi-multimode optical signal (quasi-MM signal) from the TOSA receptacle to an optical fiber, the quasi-MM signal including a lower order mode optical signal and a higher order mode optical signal and the lower order mode optical signal of the quasi-MM signal and the higher order mode optical signal of the quasi-MM signal are at least partially controlled by a core diameter of the TOSA receptacle and of a receptacle length of the TOSA receptacle;
• receiving the quasi-MM signal at a receiver optical sub assembly (ROSA) receptacle of an optical receiver;
• and
• substantially blocking the higher order mode of the quasi-MM optical signal.