| Atomic frequency standard (AFS), also called quantum frequency standard, is aproduct of combination of quantum physics and modern electronics. Since early1950's, when the first practical AFS was put into use, the AFS has been developingrapidly. Many kinds of AFS appeared. Among them, rubidium atomic frequencystandard (RAFS) has been the most widely used one due to its small volume, lowpower consumption and low production cost. The thesis firstly introduces in brief theprinciple of the RAFS. On the base of analysis of quantum system, factors whichinfluence the long term and short term stability of the RAFS were discussed, and therole of the rubidium spectral lamp of the RAFS was analyzed also.Main work of the thesis is focused on design of a rubidium spectral lamp to meetthe needs of high stability, miniaturisation and environmental adaptation of RAFS. Anew type of spectral lamp has been designed. In the design the stability of the rfexciter, the shielding manner to prevent electromagnetic disturbance, the thermalstructure of the bulb housing were carefully considered. The test results of thestability of light intensity, exciter frequency and the stimulating current showed thatthe lamp is of satisfactory performance. For the light intensity of the lamp, thestability with sample times of 104s and one day were better than 1×10-4 and 2×10-4respectively, the fluctuation was within 4×10-3, and the drift was 3×10-4/day after onemonth operation.In order to obtain a miniaturized physics package, some improvements has beenmade for the lamp. A physics package has been developed, in which the spectral lampwas utilized. The size of the physics package is 87mm(L)×40mm(H)×40mm(H), i.e.the volume is 139cm3. The frequency stability of the physics package was measuredto be 8x 10-12 and 2.5×10-12 with sample times of ls and 10s respectively. Theperformance is equivalent to that of an average commercial RAFS.
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