We regret to inform you that Intel® WiDi has been discontinued and does no longer qualify for support.
- http://www.intel.com/content/www/us/en/support/emerging-technologies/000021693.html Product Discontinuation Notice for Intel® WiDi.
Regardless, we do not have any suggestions for extending the effective range of your wireless adapter for WiDi. Perhaps you could try searching for a "Wireless Display Kit" (USB dongle + Receiver combo) with a greater range than your current wireless adapter. To verify this, you may need to engage the respective hardware vendors.