Handoff supporting apparatus and method in CDMA communication system supporting multi-frequency assignment

A method for transmitting a CDMA signal supporting a multi-frequency assignment (FAs) in a small-capacity base transceiver station (BTS) supporting only a primary frequency assignment (FA1) by producing a plurality of pilot signals corresponding to the multi-frequency assignment (FA), the BTS having a transmitter and a receiver, the method comprising the steps of:

• (a) synthesizing in the transmitter the primary frequency assignment (FA1) signal by controlling a first phase locked loop (PLL);
• (b) synthesizing in the transmitter the multi-frequency assignment (FA) signals by controlling a second phase locked loop (PLL);
• (c) generating the pilot signals corresponding to the multi-frequency assignment using the multi-frequency assignment signals generated by the second PLL;
• and,
• (c) modulating the received CDMA signal with the primary frequency assignment signal generated by the first PLL.

An apparatus for producing a plurality of pilot signals corresponding to a multi-frequency assignment (FA) to execute a hand-off in a pico base transceiver station (BTS) which only supports a primary frequency assignment (FA1) in a CDMA communication system which supports said multi-frequency assignment, said apparatus comprising:

• a first phase locked loop (PLL) synthesizer having a first PLL for synthesizing said primary frequency assignment (FA1) signal by controlling said first PLL;
• a second PLL synthesizer having a second PLL for synthesizing said multi-frequency assignment (FA) signals by controlling said second PLL;
• and,
• an up-converter for modulating transmission data with said primary frequency assignment signal provided from said first PLL synthesizer, and for producing pilot signals corresponding to said multi-frequency assignment by modulating a signal, prior to radio frequency modulation, with said multi-frequency assignment signals provided from said second PLL synthesizer to execute said hand-off in the pico BTS.

A base transceiver station (BTS) transmitter for producing a plurality of pilot signals corresponding to a multi-frequency assignment (FA) to execute a hand-off in a small-capacity BTS which only supports a primary frequency assignment (FA1) in a CDMA communication system which supports said multi-frequency assignment, said transmitter comprising:

• a first phase locked loop (PLL) synthesizer having a first PLL for synthesizing said primary frequency assignment (FA1) signal by controlling said first PLL;
• a second PLL synthesizer having a second PLL for synthesizing said multi-frequency assignment (FA) signals, in a time-hopping manner, by controlling said second PLL;
• and,
• an up-converter for modulating transmission data with said primary frequency assignment signal provided from said first PLL synthesizer to create modulated transmission data, and for producing pilot signals corresponding to said multi-frequency assignment by modulating a signal, prior to radio frequency modulation, with said multi-frequency assignment signals provided from said second PLL synthesizer, said signal to be modulated having been routed separately from said modulated transmission data.