Method, apparatus, and computer program product embodiments are disclosed to enhance capacity of a wireless communication network through spatial reuse of the shared communication medium, using an autonomous parallel operation without central coordination and header frames. Example embodiments of the invention include a signaling method that defines and sets up a Simultaneous Transmissions mode between two pairs of devices to reuse a transmission opportunity (TXOP). In example embodiments of the invention, an arrangement may be made between device pairs (each pair comprising a transmitter device and a receiver device) to allow selected pairs to communicate at a same time. The example signaling method defines example signaling for setting up simultaneous transmitter/receiver pairs in a network and operating the transmitter/receiver pairs in simultaneous transmission. If a device in a setup pair detects some other transmission than that is not allowed by one of its device pair arrangements, the device ceases its transmission.