SAW-based hybrid transceivers in slam packaging with frequency range from 200 to 1000 MHz

Short range unlicensed RF links have become extremely popular all around the world. Some examples of these links include automotive keyless entry, wireless security systems, computer data links, ID cards and remote meter reading. The new transceiver described in this paper is ideally suited for these applications. It takes advantage of a new architecture that uses a single ASIC and two SAW devices. The entire transceiver is enclosed in a surface mount package with dimensions of 10.2 by 7.06 by 2.03 mm. The device is capable of either OOK or ASK modulation with data rates exceeding 100 kb/s. The sensitivity of the receiver at 1.2 kb/s is -105 dBm. The receiver architecture takes advantage of amplifier sequencing, which allows a stable RF gain of 85 dB at the incoming RF signal frequency of interest. The sequencing of the amplifiers effectively gates crosstalk out of the SAW filters allowing out-of-band rejection levels approaching 100 dB. The transmitter uses the same two SAW devices employed in the receiver for frequency stabilization and harmonic filtering.