To solve the problem of the low energy efficiency of permutation index differentialchaos shift keying (PI-DCSK) communication systems that employ short-reference technology ,we developed an M-ary short-reference PI-DCSK ( SR-PI-DCSK) system. We shortened the chaotic sequence of the reference timeslotto less than halfofa symbolperiod and confirmed thatthe information time slot copied and spliced the permutation arrangement of the reference timeslot P times. We analyzed the energy efficiency of the SR-PI-DCSK system and derived its BER expression in a multipath Rayleigh fading channel. Further ,we verified the accuracy of the theoretical derivation using Monte Carlo simulations. The simulation results indicate thatcompared with the PI-DCSK system ,the proposed system has a betterperformance gain under the same conditions ,thus providing a candidate chaotic modulation scheme for the nextgeneration of short-range communication applications in the Internet of Things (IOT) . Moreover ,the system can effectively improve the energy efficiency and bit error rate (BER) of the PI-DCSK system withoutincreasingits structuralcomplexity while requiring the sameenergy to recover the bitinformation.