An improved MIMO system implementing joint source and channel coding in the form of Rate Compatible Punctured Convolutional Code (RCPC Code) and Unequal Error Protection (UEP) is proposed. To ensure a multiplexing gain, a layered architecture, VBLAST, is employed. Analytical BER is presented and numerical simulations are done to analyze the system performance. The proposed coding scheme allows for consistently higher error-protection level as the code rate decreases. It is also shown that whilst the lower code rates outperforms the higher ones, in terms of larger free distance and lower BER, the SNR range covered is narrower at decreasing levels of BER. This implies the potential bandwidth efficiency to be gained if the higher code rates are used for lower-priority data bits.